diff --git a/beacon_node/store/src/chunked_vector.rs b/beacon_node/store/src/chunked_vector.rs
index 8c64d4bcc0..73edfbb074 100644
--- a/beacon_node/store/src/chunked_vector.rs
+++ b/beacon_node/store/src/chunked_vector.rs
@@ -18,6 +18,7 @@ use self::UpdatePattern::*;
 use crate::*;
 use ssz::{Decode, Encode};
 use typenum::Unsigned;
+use types::historical_summary::HistoricalSummary;
 
 /// Description of how a `BeaconState` field is updated during state processing.
 ///
@@ -26,7 +27,18 @@ use typenum::Unsigned;
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum UpdatePattern {
     /// The value is updated once per `n` slots.
-    OncePerNSlots { n: u64 },
+    OncePerNSlots {
+        n: u64,
+        /// The slot at which the field begins to accumulate values.
+        ///
+        /// The field should not be read or written until `activation_slot` is reached, and the
+        /// activation slot should act as an offset when converting slots to vector indices.
+        activation_slot: Option<Slot>,
+        /// The slot at which the field ceases to accumulate values.
+        ///
+        /// If this is `None` then the field is continually updated.
+        deactivation_slot: Option<Slot>,
+    },
     /// The value is updated once per epoch, for the epoch `current_epoch - lag`.
     OncePerEpoch { lag: u64 },
 }
@@ -98,12 +110,30 @@ pub trait Field<E: EthSpec>: Copy {
     fn start_and_end_vindex(current_slot: Slot, spec: &ChainSpec) -> (usize, usize) {
         // We take advantage of saturating subtraction on slots and epochs
         match Self::update_pattern(spec) {
-            OncePerNSlots { n } => {
+            OncePerNSlots {
+                n,
+                activation_slot,
+                deactivation_slot,
+            } => {
                 // Per-slot changes exclude the index for the current slot, because
                 // it won't be set until the slot completes (think of `state_roots`, `block_roots`).
                 // This also works for the `historical_roots` because at the `n`th slot, the 0th
                 // entry of the list is created, and before that the list is empty.
-                let end_vindex = current_slot / n;
+                //
+                // To account for the switch from historical roots to historical summaries at
+                // Capella we also modify the current slot by the activation and deactivation slots.
+                // The activation slot acts as an offset (subtraction) while the deactivation slot
+                // acts as a clamp (min).
+                let slot_with_clamp = deactivation_slot.map_or(current_slot, |deactivation_slot| {
+                    std::cmp::min(current_slot, deactivation_slot)
+                });
+                let slot_with_clamp_and_offset = if let Some(activation_slot) = activation_slot {
+                    slot_with_clamp - activation_slot
+                } else {
+                    // Return (0, 0) to indicate that the field should not be read/written.
+                    return (0, 0);
+                };
+                let end_vindex = slot_with_clamp_and_offset / n;
                 let start_vindex = end_vindex - Self::Length::to_u64();
                 (start_vindex.as_usize(), end_vindex.as_usize())
             }
@@ -295,7 +325,11 @@ field!(
     Hash256,
     T::SlotsPerHistoricalRoot,
     DBColumn::BeaconBlockRoots,
-    |_| OncePerNSlots { n: 1 },
+    |_| OncePerNSlots {
+        n: 1,
+        activation_slot: Some(Slot::new(0)),
+        deactivation_slot: None
+    },
     |state: &BeaconState<_>, index, _| safe_modulo_index(state.block_roots(), index)
 );
 
@@ -305,7 +339,11 @@ field!(
     Hash256,
     T::SlotsPerHistoricalRoot,
     DBColumn::BeaconStateRoots,
-    |_| OncePerNSlots { n: 1 },
+    |_| OncePerNSlots {
+        n: 1,
+        activation_slot: Some(Slot::new(0)),
+        deactivation_slot: None,
+    },
     |state: &BeaconState<_>, index, _| safe_modulo_index(state.state_roots(), index)
 );
 
@@ -315,8 +353,12 @@ field!(
     Hash256,
     T::HistoricalRootsLimit,
     DBColumn::BeaconHistoricalRoots,
-    |_| OncePerNSlots {
-        n: T::SlotsPerHistoricalRoot::to_u64()
+    |spec: &ChainSpec| OncePerNSlots {
+        n: T::SlotsPerHistoricalRoot::to_u64(),
+        activation_slot: Some(Slot::new(0)),
+        deactivation_slot: spec
+            .capella_fork_epoch
+            .map(|fork_epoch| fork_epoch.start_slot(T::slots_per_epoch())),
     },
     |state: &BeaconState<_>, index, _| safe_modulo_index(state.historical_roots(), index)
 );
@@ -331,6 +373,27 @@ field!(
     |state: &BeaconState<_>, index, _| safe_modulo_index(state.randao_mixes(), index)
 );
 
+field!(
+    HistoricalSummaries,
+    VariableLengthField,
+    HistoricalSummary,
+    T::HistoricalRootsLimit,
+    DBColumn::BeaconHistoricalSummaries,
+    |spec: &ChainSpec| OncePerNSlots {
+        n: T::SlotsPerHistoricalRoot::to_u64(),
+        activation_slot: spec
+            .capella_fork_epoch
+            .map(|fork_epoch| fork_epoch.start_slot(T::slots_per_epoch())),
+        deactivation_slot: None,
+    },
+    |state: &BeaconState<_>, index, _| safe_modulo_index(
+        state
+            .historical_summaries()
+            .map_err(|_| ChunkError::InvalidFork)?,
+        index
+    )
+);
+
 pub fn store_updated_vector<F: Field<E>, E: EthSpec, S: KeyValueStore<E>>(
     field: F,
     store: &S,
@@ -679,6 +742,7 @@ pub enum ChunkError {
         end_vindex: usize,
         length: usize,
     },
+    InvalidFork,
 }
 
 #[cfg(test)]
diff --git a/beacon_node/store/src/hot_cold_store.rs b/beacon_node/store/src/hot_cold_store.rs
index 4600e5e826..93af0ca184 100644
--- a/beacon_node/store/src/hot_cold_store.rs
+++ b/beacon_node/store/src/hot_cold_store.rs
@@ -1,5 +1,5 @@
 use crate::chunked_vector::{
-    store_updated_vector, BlockRoots, HistoricalRoots, RandaoMixes, StateRoots,
+    store_updated_vector, BlockRoots, HistoricalRoots, HistoricalSummaries, RandaoMixes, StateRoots,
 };
 use crate::config::{
     OnDiskStoreConfig, StoreConfig, DEFAULT_SLOTS_PER_RESTORE_POINT,
@@ -948,6 +948,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         store_updated_vector(StateRoots, db, state, &self.spec, ops)?;
         store_updated_vector(HistoricalRoots, db, state, &self.spec, ops)?;
         store_updated_vector(RandaoMixes, db, state, &self.spec, ops)?;
+        store_updated_vector(HistoricalSummaries, db, state, &self.spec, ops)?;
 
         // 3. Store restore point.
         let restore_point_index = state.slot().as_u64() / self.config.slots_per_restore_point;
@@ -1002,6 +1003,7 @@ impl<E: EthSpec, Hot: ItemStore<E>, Cold: ItemStore<E>> HotColdDB<E, Hot, Cold>
         partial_state.load_state_roots(&self.cold_db, &self.spec)?;
         partial_state.load_historical_roots(&self.cold_db, &self.spec)?;
         partial_state.load_randao_mixes(&self.cold_db, &self.spec)?;
+        partial_state.load_historical_summaries(&self.cold_db, &self.spec)?;
 
         partial_state.try_into()
     }
diff --git a/beacon_node/store/src/lib.rs b/beacon_node/store/src/lib.rs
index d9041dd636..9db5f45ece 100644
--- a/beacon_node/store/src/lib.rs
+++ b/beacon_node/store/src/lib.rs
@@ -214,6 +214,8 @@ pub enum DBColumn {
     /// For Optimistically Imported Merge Transition Blocks
     #[strum(serialize = "otb")]
     OptimisticTransitionBlock,
+    #[strum(serialize = "bhs")]
+    BeaconHistoricalSummaries,
 }
 
 /// A block from the database, which might have an execution payload or not.
diff --git a/beacon_node/store/src/partial_beacon_state.rs b/beacon_node/store/src/partial_beacon_state.rs
index ca35bc0b22..55697bd316 100644
--- a/beacon_node/store/src/partial_beacon_state.rs
+++ b/beacon_node/store/src/partial_beacon_state.rs
@@ -1,12 +1,13 @@
 use crate::chunked_vector::{
-    load_variable_list_from_db, load_vector_from_db, BlockRoots, HistoricalRoots, RandaoMixes,
-    StateRoots,
+    load_variable_list_from_db, load_vector_from_db, BlockRoots, HistoricalRoots,
+    HistoricalSummaries, RandaoMixes, StateRoots,
 };
 use crate::{get_key_for_col, DBColumn, Error, KeyValueStore, KeyValueStoreOp};
 use ssz::{Decode, DecodeError, Encode};
 use ssz_derive::{Decode, Encode};
 use std::convert::TryInto;
 use std::sync::Arc;
+use types::historical_summary::HistoricalSummary;
 use types::superstruct;
 use types::*;
 
@@ -104,16 +105,20 @@ where
     )]
     pub latest_execution_payload_header: ExecutionPayloadHeaderEip4844<T>,
 
-    // Withdrawals
+    // Capella
     #[superstruct(only(Capella, Eip4844))]
     pub next_withdrawal_index: u64,
     #[superstruct(only(Capella, Eip4844))]
     pub next_withdrawal_validator_index: u64,
+
+    #[ssz(skip_serializing, skip_deserializing)]
+    #[superstruct(only(Capella, Eip4844))]
+    pub historical_summaries: Option<VariableList<HistoricalSummary, T::HistoricalRootsLimit>>,
 }
 
 /// Implement the conversion function from BeaconState -> PartialBeaconState.
 macro_rules! impl_from_state_forgetful {
-    ($s:ident, $outer:ident, $variant_name:ident, $struct_name:ident, [$($extra_fields:ident),*]) => {
+    ($s:ident, $outer:ident, $variant_name:ident, $struct_name:ident, [$($extra_fields:ident),*], [$($extra_fields_opt:ident),*]) => {
         PartialBeaconState::$variant_name($struct_name {
             // Versioning
             genesis_time: $s.genesis_time,
@@ -154,6 +159,11 @@ macro_rules! impl_from_state_forgetful {
             // Variant-specific fields
             $(
                 $extra_fields: $s.$extra_fields.clone()
+            ),*,
+
+            // Variant-specific optional
+            $(
+                $extra_fields_opt: None
             ),*
         })
     }
@@ -168,7 +178,8 @@ impl<T: EthSpec> PartialBeaconState<T> {
                 outer,
                 Base,
                 PartialBeaconStateBase,
-                [previous_epoch_attestations, current_epoch_attestations]
+                [previous_epoch_attestations, current_epoch_attestations],
+                []
             ),
             BeaconState::Altair(s) => impl_from_state_forgetful!(
                 s,
@@ -181,7 +192,8 @@ impl<T: EthSpec> PartialBeaconState<T> {
                     current_sync_committee,
                     next_sync_committee,
                     inactivity_scores
-                ]
+                ],
+                []
             ),
             BeaconState::Merge(s) => impl_from_state_forgetful!(
                 s,
@@ -195,7 +207,8 @@ impl<T: EthSpec> PartialBeaconState<T> {
                     next_sync_committee,
                     inactivity_scores,
                     latest_execution_payload_header
-                ]
+                ],
+                []
             ),
             BeaconState::Capella(s) => impl_from_state_forgetful!(
                 s,
@@ -211,7 +224,8 @@ impl<T: EthSpec> PartialBeaconState<T> {
                     latest_execution_payload_header,
                     next_withdrawal_index,
                     next_withdrawal_validator_index
-                ]
+                ],
+                [historical_summaries]
             ),
             BeaconState::Eip4844(s) => impl_from_state_forgetful!(
                 s,
@@ -227,7 +241,8 @@ impl<T: EthSpec> PartialBeaconState<T> {
                     latest_execution_payload_header,
                     next_withdrawal_index,
                     next_withdrawal_validator_index
-                ]
+                ],
+                [historical_summaries]
             ),
         }
     }
@@ -303,6 +318,23 @@ impl<T: EthSpec> PartialBeaconState<T> {
         Ok(())
     }
 
+    pub fn load_historical_summaries<S: KeyValueStore<T>>(
+        &mut self,
+        store: &S,
+        spec: &ChainSpec,
+    ) -> Result<(), Error> {
+        let slot = self.slot();
+        if let Ok(historical_summaries) = self.historical_summaries_mut() {
+            if historical_summaries.is_none() {
+                *historical_summaries =
+                    Some(load_variable_list_from_db::<HistoricalSummaries, T, _>(
+                        store, slot, spec,
+                    )?);
+            }
+        }
+        Ok(())
+    }
+
     pub fn load_randao_mixes<S: KeyValueStore<T>>(
         &mut self,
         store: &S,
@@ -326,7 +358,7 @@ impl<T: EthSpec> PartialBeaconState<T> {
 
 /// Implement the conversion from PartialBeaconState -> BeaconState.
 macro_rules! impl_try_into_beacon_state {
-    ($inner:ident, $variant_name:ident, $struct_name:ident, [$($extra_fields:ident),*]) => {
+    ($inner:ident, $variant_name:ident, $struct_name:ident, [$($extra_fields:ident),*], [$($extra_opt_fields:ident),*]) => {
         BeaconState::$variant_name($struct_name {
             // Versioning
             genesis_time: $inner.genesis_time,
@@ -371,6 +403,11 @@ macro_rules! impl_try_into_beacon_state {
             // Variant-specific fields
             $(
                 $extra_fields: $inner.$extra_fields
+            ),*,
+
+            // Variant-specific optional fields
+            $(
+                $extra_opt_fields: unpack_field($inner.$extra_opt_fields)?
             ),*
         })
     }
@@ -389,7 +426,8 @@ impl<E: EthSpec> TryInto<BeaconState<E>> for PartialBeaconState<E> {
                 inner,
                 Base,
                 BeaconStateBase,
-                [previous_epoch_attestations, current_epoch_attestations]
+                [previous_epoch_attestations, current_epoch_attestations],
+                []
             ),
             PartialBeaconState::Altair(inner) => impl_try_into_beacon_state!(
                 inner,
@@ -401,7 +439,8 @@ impl<E: EthSpec> TryInto<BeaconState<E>> for PartialBeaconState<E> {
                     current_sync_committee,
                     next_sync_committee,
                     inactivity_scores
-                ]
+                ],
+                []
             ),
             PartialBeaconState::Merge(inner) => impl_try_into_beacon_state!(
                 inner,
@@ -414,7 +453,8 @@ impl<E: EthSpec> TryInto<BeaconState<E>> for PartialBeaconState<E> {
                     next_sync_committee,
                     inactivity_scores,
                     latest_execution_payload_header
-                ]
+                ],
+                []
             ),
             PartialBeaconState::Capella(inner) => impl_try_into_beacon_state!(
                 inner,
@@ -429,7 +469,8 @@ impl<E: EthSpec> TryInto<BeaconState<E>> for PartialBeaconState<E> {
                     latest_execution_payload_header,
                     next_withdrawal_index,
                     next_withdrawal_validator_index
-                ]
+                ],
+                [historical_summaries]
             ),
             PartialBeaconState::Eip4844(inner) => impl_try_into_beacon_state!(
                 inner,
@@ -444,7 +485,8 @@ impl<E: EthSpec> TryInto<BeaconState<E>> for PartialBeaconState<E> {
                     latest_execution_payload_header,
                     next_withdrawal_index,
                     next_withdrawal_validator_index
-                ]
+                ],
+                [historical_summaries]
             ),
         };
         Ok(state)
diff --git a/consensus/state_processing/src/per_epoch_processing.rs b/consensus/state_processing/src/per_epoch_processing.rs
index f227b82863..996e39c27f 100644
--- a/consensus/state_processing/src/per_epoch_processing.rs
+++ b/consensus/state_processing/src/per_epoch_processing.rs
@@ -3,14 +3,16 @@
 pub use epoch_processing_summary::EpochProcessingSummary;
 use errors::EpochProcessingError as Error;
 pub use justification_and_finalization_state::JustificationAndFinalizationState;
-pub use registry_updates::process_registry_updates;
 use safe_arith::SafeArith;
-pub use slashings::process_slashings;
 use types::{BeaconState, ChainSpec, EthSpec};
+
+pub use registry_updates::process_registry_updates;
+pub use slashings::process_slashings;
 pub use weigh_justification_and_finalization::weigh_justification_and_finalization;
 
 pub mod altair;
 pub mod base;
+pub mod capella;
 pub mod effective_balance_updates;
 pub mod epoch_processing_summary;
 pub mod errors;
@@ -37,10 +39,8 @@ pub fn process_epoch<T: EthSpec>(
 
     match state {
         BeaconState::Base(_) => base::process_epoch(state, spec),
-        BeaconState::Altair(_)
-        | BeaconState::Merge(_)
-        | BeaconState::Capella(_)
-        | BeaconState::Eip4844(_) => altair::process_epoch(state, spec),
+        BeaconState::Altair(_) | BeaconState::Merge(_) => altair::process_epoch(state, spec),
+        BeaconState::Capella(_) | BeaconState::Eip4844(_) => capella::process_epoch(state, spec),
     }
 }
 
diff --git a/consensus/state_processing/src/per_epoch_processing/capella.rs b/consensus/state_processing/src/per_epoch_processing/capella.rs
new file mode 100644
index 0000000000..aaf301f29e
--- /dev/null
+++ b/consensus/state_processing/src/per_epoch_processing/capella.rs
@@ -0,0 +1,78 @@
+use super::altair::inactivity_updates::process_inactivity_updates;
+use super::altair::justification_and_finalization::process_justification_and_finalization;
+use super::altair::participation_cache::ParticipationCache;
+use super::altair::participation_flag_updates::process_participation_flag_updates;
+use super::altair::rewards_and_penalties::process_rewards_and_penalties;
+use super::altair::sync_committee_updates::process_sync_committee_updates;
+use super::{process_registry_updates, process_slashings, EpochProcessingSummary, Error};
+use crate::per_epoch_processing::{
+    effective_balance_updates::process_effective_balance_updates,
+    resets::{process_eth1_data_reset, process_randao_mixes_reset, process_slashings_reset},
+};
+use types::{BeaconState, ChainSpec, EthSpec, RelativeEpoch};
+
+pub use historical_summaries_update::process_historical_summaries_update;
+
+mod historical_summaries_update;
+
+pub fn process_epoch<T: EthSpec>(
+    state: &mut BeaconState<T>,
+    spec: &ChainSpec,
+) -> Result<EpochProcessingSummary<T>, Error> {
+    // Ensure the committee caches are built.
+    state.build_committee_cache(RelativeEpoch::Previous, spec)?;
+    state.build_committee_cache(RelativeEpoch::Current, spec)?;
+    state.build_committee_cache(RelativeEpoch::Next, spec)?;
+
+    // Pre-compute participating indices and total balances.
+    let participation_cache = ParticipationCache::new(state, spec)?;
+    let sync_committee = state.current_sync_committee()?.clone();
+
+    // Justification and finalization.
+    let justification_and_finalization_state =
+        process_justification_and_finalization(state, &participation_cache)?;
+    justification_and_finalization_state.apply_changes_to_state(state);
+
+    process_inactivity_updates(state, &participation_cache, spec)?;
+
+    // Rewards and Penalties.
+    process_rewards_and_penalties(state, &participation_cache, spec)?;
+
+    // Registry Updates.
+    process_registry_updates(state, spec)?;
+
+    // Slashings.
+    process_slashings(
+        state,
+        participation_cache.current_epoch_total_active_balance(),
+        spec,
+    )?;
+
+    // Reset eth1 data votes.
+    process_eth1_data_reset(state)?;
+
+    // Update effective balances with hysteresis (lag).
+    process_effective_balance_updates(state, spec)?;
+
+    // Reset slashings
+    process_slashings_reset(state)?;
+
+    // Set randao mix
+    process_randao_mixes_reset(state)?;
+
+    // Set historical summaries accumulator
+    process_historical_summaries_update(state)?;
+
+    // Rotate current/previous epoch participation
+    process_participation_flag_updates(state)?;
+
+    process_sync_committee_updates(state, spec)?;
+
+    // Rotate the epoch caches to suit the epoch transition.
+    state.advance_caches(spec)?;
+
+    Ok(EpochProcessingSummary::Altair {
+        participation_cache,
+        sync_committee,
+    })
+}
diff --git a/consensus/state_processing/src/per_epoch_processing/capella/historical_summaries_update.rs b/consensus/state_processing/src/per_epoch_processing/capella/historical_summaries_update.rs
new file mode 100644
index 0000000000..9a87ceb605
--- /dev/null
+++ b/consensus/state_processing/src/per_epoch_processing/capella/historical_summaries_update.rs
@@ -0,0 +1,23 @@
+use crate::EpochProcessingError;
+use safe_arith::SafeArith;
+use types::historical_summary::HistoricalSummary;
+use types::{BeaconState, EthSpec};
+
+pub fn process_historical_summaries_update<T: EthSpec>(
+    state: &mut BeaconState<T>,
+) -> Result<(), EpochProcessingError> {
+    // Set historical block root accumulator.
+    let next_epoch = state.next_epoch()?;
+    if next_epoch
+        .as_u64()
+        .safe_rem((T::slots_per_historical_root() as u64).safe_div(T::slots_per_epoch())?)?
+        == 0
+    {
+        let summary = HistoricalSummary::new(state);
+        return state
+            .historical_summaries_mut()?
+            .push(summary)
+            .map_err(Into::into);
+    }
+    Ok(())
+}
diff --git a/consensus/state_processing/src/upgrade/capella.rs b/consensus/state_processing/src/upgrade/capella.rs
index dc759b384d..3b933fac37 100644
--- a/consensus/state_processing/src/upgrade/capella.rs
+++ b/consensus/state_processing/src/upgrade/capella.rs
@@ -1,3 +1,4 @@
+use ssz_types::VariableList;
 use std::mem;
 use types::{BeaconState, BeaconStateCapella, BeaconStateError as Error, ChainSpec, EthSpec, Fork};
 
@@ -55,9 +56,10 @@ pub fn upgrade_to_capella<E: EthSpec>(
         next_sync_committee: pre.next_sync_committee.clone(),
         // Execution
         latest_execution_payload_header: pre.latest_execution_payload_header.upgrade_to_capella(),
-        // Withdrawals
+        // Capella
         next_withdrawal_index: 0,
         next_withdrawal_validator_index: 0,
+        historical_summaries: VariableList::default(),
         // Caches
         total_active_balance: pre.total_active_balance,
         committee_caches: mem::take(&mut pre.committee_caches),
diff --git a/consensus/state_processing/src/upgrade/eip4844.rs b/consensus/state_processing/src/upgrade/eip4844.rs
index e829c01e7e..4f6ff9d194 100644
--- a/consensus/state_processing/src/upgrade/eip4844.rs
+++ b/consensus/state_processing/src/upgrade/eip4844.rs
@@ -57,9 +57,10 @@ pub fn upgrade_to_eip4844<E: EthSpec>(
         next_sync_committee: pre.next_sync_committee.clone(),
         // Execution
         latest_execution_payload_header: pre.latest_execution_payload_header.upgrade_to_eip4844(),
-        // Withdrawals
+        // Capella
         next_withdrawal_index: pre.next_withdrawal_index,
         next_withdrawal_validator_index: pre.next_withdrawal_validator_index,
+        historical_summaries: pre.historical_summaries.clone(),
         // Caches
         total_active_balance: pre.total_active_balance,
         committee_caches: mem::take(&mut pre.committee_caches),
diff --git a/consensus/types/src/beacon_state.rs b/consensus/types/src/beacon_state.rs
index 625ff3d174..f51a7bf9fb 100644
--- a/consensus/types/src/beacon_state.rs
+++ b/consensus/types/src/beacon_state.rs
@@ -14,6 +14,7 @@ use ssz::{ssz_encode, Decode, DecodeError, Encode};
 use ssz_derive::{Decode, Encode};
 use ssz_types::{typenum::Unsigned, BitVector, FixedVector};
 use std::convert::TryInto;
+use std::hash::Hash;
 use std::{fmt, mem, sync::Arc};
 use superstruct::superstruct;
 use swap_or_not_shuffle::compute_shuffled_index;
@@ -25,6 +26,7 @@ pub use self::committee_cache::{
     compute_committee_index_in_epoch, compute_committee_range_in_epoch, epoch_committee_count,
     CommitteeCache,
 };
+use crate::historical_summary::HistoricalSummary;
 pub use clone_config::CloneConfig;
 pub use eth_spec::*;
 pub use iter::BlockRootsIter;
@@ -223,6 +225,7 @@ where
     pub block_roots: FixedVector<Hash256, T::SlotsPerHistoricalRoot>,
     #[compare_fields(as_slice)]
     pub state_roots: FixedVector<Hash256, T::SlotsPerHistoricalRoot>,
+    // Frozen in Capella, replaced by historical_summaries
     pub historical_roots: VariableList<Hash256, T::HistoricalRootsLimit>,
 
     // Ethereum 1.0 chain data
@@ -296,11 +299,14 @@ where
     )]
     pub latest_execution_payload_header: ExecutionPayloadHeaderEip4844<T>,
 
-    // Withdrawals
+    // Capella
     #[superstruct(only(Capella, Eip4844), partial_getter(copy))]
     pub next_withdrawal_index: u64,
     #[superstruct(only(Capella, Eip4844), partial_getter(copy))]
     pub next_withdrawal_validator_index: u64,
+    // Deep history valid from Capella onwards.
+    #[superstruct(only(Capella, Eip4844))]
+    pub historical_summaries: VariableList<HistoricalSummary, T::HistoricalRootsLimit>,
 
     // Caching (not in the spec)
     #[serde(skip_serializing, skip_deserializing)]
diff --git a/consensus/types/src/beacon_state/tree_hash_cache.rs b/consensus/types/src/beacon_state/tree_hash_cache.rs
index 4cfc684f4d..5515fb753a 100644
--- a/consensus/types/src/beacon_state/tree_hash_cache.rs
+++ b/consensus/types/src/beacon_state/tree_hash_cache.rs
@@ -3,6 +3,7 @@
 #![allow(clippy::indexing_slicing)]
 
 use super::Error;
+use crate::historical_summary::HistoricalSummaryCache;
 use crate::{BeaconState, EthSpec, Hash256, ParticipationList, Slot, Unsigned, Validator};
 use cached_tree_hash::{int_log, CacheArena, CachedTreeHash, TreeHashCache};
 use rayon::prelude::*;
@@ -142,6 +143,7 @@ pub struct BeaconTreeHashCacheInner<T: EthSpec> {
     block_roots: TreeHashCache,
     state_roots: TreeHashCache,
     historical_roots: TreeHashCache,
+    historical_summaries: OptionalTreeHashCache,
     balances: TreeHashCache,
     randao_mixes: TreeHashCache,
     slashings: TreeHashCache,
@@ -164,6 +166,14 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
         let historical_roots = state
             .historical_roots()
             .new_tree_hash_cache(&mut fixed_arena);
+        let historical_summaries = OptionalTreeHashCache::new(
+            state
+                .historical_summaries()
+                .ok()
+                .map(HistoricalSummaryCache::new)
+                .as_ref(),
+        );
+
         let randao_mixes = state.randao_mixes().new_tree_hash_cache(&mut fixed_arena);
 
         let validators = ValidatorsListTreeHashCache::new::<T>(state.validators());
@@ -200,6 +210,7 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
             block_roots,
             state_roots,
             historical_roots,
+            historical_summaries,
             balances,
             randao_mixes,
             slashings,
@@ -249,6 +260,7 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
                 .slashings()
                 .recalculate_tree_hash_root(&mut self.slashings_arena, &mut self.slashings)?,
         ];
+
         // Participation
         if let BeaconState::Base(state) = state {
             leaves.push(state.previous_epoch_attestations.tree_hash_root());
@@ -291,6 +303,24 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
         if let Ok(payload_header) = state.latest_execution_payload_header() {
             leaves.push(payload_header.tree_hash_root());
         }
+
+        // Withdrawal indices (Capella and later).
+        if let Ok(next_withdrawal_index) = state.next_withdrawal_index() {
+            leaves.push(next_withdrawal_index.tree_hash_root());
+        }
+        if let Ok(next_withdrawal_validator_index) = state.next_withdrawal_validator_index() {
+            leaves.push(next_withdrawal_validator_index.tree_hash_root());
+        }
+
+        // Historical roots/summaries (Capella and later).
+        if let Ok(historical_summaries) = state.historical_summaries() {
+            leaves.push(
+                self.historical_summaries.recalculate_tree_hash_root(
+                    &HistoricalSummaryCache::new(historical_summaries),
+                )?,
+            );
+        }
+
         Ok(leaves)
     }
 
@@ -335,14 +365,6 @@ impl<T: EthSpec> BeaconTreeHashCacheInner<T> {
             hasher.write(leaf.as_bytes())?;
         }
 
-        // Withdrawal indices (Capella and later).
-        if let Ok(next_withdrawal_index) = state.next_withdrawal_index() {
-            hasher.write(next_withdrawal_index.tree_hash_root().as_bytes())?;
-        }
-        if let Ok(next_withdrawal_validator_index) = state.next_withdrawal_validator_index() {
-            hasher.write(next_withdrawal_validator_index.tree_hash_root().as_bytes())?;
-        }
-
         let root = hasher.finish()?;
 
         self.previous_state = Some((root, state.slot()));
diff --git a/consensus/types/src/historical_summary.rs b/consensus/types/src/historical_summary.rs
new file mode 100644
index 0000000000..1f79ee49fa
--- /dev/null
+++ b/consensus/types/src/historical_summary.rs
@@ -0,0 +1,88 @@
+use crate::test_utils::TestRandom;
+use crate::Unsigned;
+use crate::{BeaconState, EthSpec, Hash256};
+use cached_tree_hash::Error;
+use cached_tree_hash::{int_log, CacheArena, CachedTreeHash, TreeHashCache};
+use compare_fields_derive::CompareFields;
+use serde_derive::{Deserialize, Serialize};
+use ssz_derive::{Decode, Encode};
+use ssz_types::VariableList;
+use test_random_derive::TestRandom;
+use tree_hash::{mix_in_length, TreeHash, BYTES_PER_CHUNK};
+use tree_hash_derive::TreeHash;
+
+/// `HistoricalSummary` matches the components of the phase0 `HistoricalBatch`
+/// making the two hash_tree_root-compatible. This struct is introduced into the beacon state
+/// in the Capella hard fork.
+///
+/// https://github.com/ethereum/consensus-specs/blob/dev/specs/capella/beacon-chain.md#historicalsummary
+#[derive(
+    Debug,
+    PartialEq,
+    Serialize,
+    Deserialize,
+    Encode,
+    Decode,
+    TreeHash,
+    TestRandom,
+    CompareFields,
+    Clone,
+    Copy,
+    Default,
+)]
+pub struct HistoricalSummary {
+    block_summary_root: Hash256,
+    state_summary_root: Hash256,
+}
+
+impl HistoricalSummary {
+    pub fn new<T: EthSpec>(state: &BeaconState<T>) -> Self {
+        Self {
+            block_summary_root: state.block_roots().tree_hash_root(),
+            state_summary_root: state.state_roots().tree_hash_root(),
+        }
+    }
+}
+
+/// Wrapper type allowing the implementation of `CachedTreeHash`.
+#[derive(Debug)]
+pub struct HistoricalSummaryCache<'a, N: Unsigned> {
+    pub inner: &'a VariableList<HistoricalSummary, N>,
+}
+
+impl<'a, N: Unsigned> HistoricalSummaryCache<'a, N> {
+    pub fn new(inner: &'a VariableList<HistoricalSummary, N>) -> Self {
+        Self { inner }
+    }
+
+    #[allow(clippy::len_without_is_empty)]
+    pub fn len(&self) -> usize {
+        self.inner.len()
+    }
+}
+
+impl<'a, N: Unsigned> CachedTreeHash<TreeHashCache> for HistoricalSummaryCache<'a, N> {
+    fn new_tree_hash_cache(&self, arena: &mut CacheArena) -> TreeHashCache {
+        TreeHashCache::new(arena, int_log(N::to_usize()), self.len())
+    }
+
+    fn recalculate_tree_hash_root(
+        &self,
+        arena: &mut CacheArena,
+        cache: &mut TreeHashCache,
+    ) -> Result<Hash256, Error> {
+        Ok(mix_in_length(
+            &cache.recalculate_merkle_root(arena, leaf_iter(self.inner))?,
+            self.len(),
+        ))
+    }
+}
+
+pub fn leaf_iter(
+    values: &[HistoricalSummary],
+) -> impl Iterator<Item = [u8; BYTES_PER_CHUNK]> + ExactSizeIterator + '_ {
+    values
+        .iter()
+        .map(|value| value.tree_hash_root())
+        .map(Hash256::to_fixed_bytes)
+}
diff --git a/consensus/types/src/lib.rs b/consensus/types/src/lib.rs
index 6cbb9568da..f0806e35ad 100644
--- a/consensus/types/src/lib.rs
+++ b/consensus/types/src/lib.rs
@@ -49,6 +49,7 @@ pub mod fork_name;
 pub mod free_attestation;
 pub mod graffiti;
 pub mod historical_batch;
+pub mod historical_summary;
 pub mod indexed_attestation;
 pub mod light_client_bootstrap;
 pub mod light_client_finality_update;
diff --git a/lcli/src/main.rs b/lcli/src/main.rs
index 238c7e9f16..3af485be10 100644
--- a/lcli/src/main.rs
+++ b/lcli/src/main.rs
@@ -741,7 +741,6 @@ fn main() {
                         .value_name("PATH")
                         .takes_value(true)
                         .conflicts_with("beacon-url")
-                        .requires("pre-state-path")
                         .help("Path to load a SignedBeaconBlock from file as SSZ."),
                 )
                 .arg(
diff --git a/testing/ef_tests/Makefile b/testing/ef_tests/Makefile
index 69b18ee747..354631e5c3 100644
--- a/testing/ef_tests/Makefile
+++ b/testing/ef_tests/Makefile
@@ -1,4 +1,4 @@
-TESTS_TAG := v1.3.0-alpha.2
+TESTS_TAG := v1.3.0-rc.0
 TESTS = general minimal mainnet
 TARBALLS = $(patsubst %,%-$(TESTS_TAG).tar.gz,$(TESTS))
 
diff --git a/testing/ef_tests/check_all_files_accessed.py b/testing/ef_tests/check_all_files_accessed.py
index 04f45ac5da..b098241366 100755
--- a/testing/ef_tests/check_all_files_accessed.py
+++ b/testing/ef_tests/check_all_files_accessed.py
@@ -41,8 +41,6 @@ excluded_paths = [
     "tests/.*/.*/ssz_static/LightClientFinalityUpdate",
     # Eip4844 tests are disabled for now.
     "tests/.*/eip4844",
-    # Capella tests are disabled for now.
-    "tests/.*/capella",
     # One of the EF researchers likes to pack the tarballs on a Mac
     ".*\.DS_Store.*",
     # More Mac weirdness.
diff --git a/testing/ef_tests/src/cases/epoch_processing.rs b/testing/ef_tests/src/cases/epoch_processing.rs
index b0e16e12c7..59a8ebd41c 100644
--- a/testing/ef_tests/src/cases/epoch_processing.rs
+++ b/testing/ef_tests/src/cases/epoch_processing.rs
@@ -5,6 +5,7 @@ use crate::decode::{ssz_decode_state, yaml_decode_file};
 use crate::type_name;
 use crate::type_name::TypeName;
 use serde_derive::Deserialize;
+use state_processing::per_epoch_processing::capella::process_historical_summaries_update;
 use state_processing::per_epoch_processing::{
     altair, base,
     effective_balance_updates::process_effective_balance_updates,
@@ -57,6 +58,8 @@ pub struct RandaoMixesReset;
 #[derive(Debug)]
 pub struct HistoricalRootsUpdate;
 #[derive(Debug)]
+pub struct HistoricalSummariesUpdate;
+#[derive(Debug)]
 pub struct ParticipationRecordUpdates;
 #[derive(Debug)]
 pub struct SyncCommitteeUpdates;
@@ -77,6 +80,7 @@ type_name!(EffectiveBalanceUpdates, "effective_balance_updates");
 type_name!(SlashingsReset, "slashings_reset");
 type_name!(RandaoMixesReset, "randao_mixes_reset");
 type_name!(HistoricalRootsUpdate, "historical_roots_update");
+type_name!(HistoricalSummariesUpdate, "historical_summaries_update");
 type_name!(ParticipationRecordUpdates, "participation_record_updates");
 type_name!(SyncCommitteeUpdates, "sync_committee_updates");
 type_name!(InactivityUpdates, "inactivity_updates");
@@ -194,7 +198,23 @@ impl<E: EthSpec> EpochTransition<E> for RandaoMixesReset {
 
 impl<E: EthSpec> EpochTransition<E> for HistoricalRootsUpdate {
     fn run(state: &mut BeaconState<E>, _spec: &ChainSpec) -> Result<(), EpochProcessingError> {
-        process_historical_roots_update(state)
+        match state {
+            BeaconState::Base(_) | BeaconState::Altair(_) | BeaconState::Merge(_) => {
+                process_historical_roots_update(state)
+            }
+            _ => Ok(()),
+        }
+    }
+}
+
+impl<E: EthSpec> EpochTransition<E> for HistoricalSummariesUpdate {
+    fn run(state: &mut BeaconState<E>, _spec: &ChainSpec) -> Result<(), EpochProcessingError> {
+        match state {
+            BeaconState::Capella(_) | BeaconState::Eip4844(_) => {
+                process_historical_summaries_update(state)
+            }
+            _ => Ok(()),
+        }
     }
 }
 
@@ -287,10 +307,16 @@ impl<E: EthSpec, T: EpochTransition<E>> Case for EpochProcessing<E, T> {
                 T::name() != "sync_committee_updates"
                     && T::name() != "inactivity_updates"
                     && T::name() != "participation_flag_updates"
+                    && T::name() != "historical_summaries_update"
             }
             // No phase0 tests for Altair and later.
-            ForkName::Altair | ForkName::Merge | ForkName::Capella => {
+            ForkName::Altair | ForkName::Merge => {
                 T::name() != "participation_record_updates"
+                    && T::name() != "historical_summaries_update"
+            }
+            ForkName::Capella => {
+                T::name() != "participation_record_updates"
+                    && T::name() != "historical_roots_update"
             }
             ForkName::Eip4844 => false, // TODO: revisit when tests are out
         }
diff --git a/testing/ef_tests/src/handler.rs b/testing/ef_tests/src/handler.rs
index 66f81616b7..07db7cd2a1 100644
--- a/testing/ef_tests/src/handler.rs
+++ b/testing/ef_tests/src/handler.rs
@@ -374,6 +374,11 @@ impl<E: EthSpec + TypeName> Handler for SanitySlotsHandler<E> {
     fn handler_name(&self) -> String {
         "slots".into()
     }
+
+    fn is_enabled_for_fork(&self, fork_name: ForkName) -> bool {
+        // Some sanity tests compute sync committees, which requires real crypto.
+        fork_name == ForkName::Base || cfg!(not(feature = "fake_crypto"))
+    }
 }
 
 #[derive(Derivative)]
diff --git a/testing/ef_tests/src/lib.rs b/testing/ef_tests/src/lib.rs
index f52b7bca17..5ab2b4b7b4 100644
--- a/testing/ef_tests/src/lib.rs
+++ b/testing/ef_tests/src/lib.rs
@@ -1,10 +1,10 @@
 pub use case_result::CaseResult;
 pub use cases::WithdrawalsPayload;
 pub use cases::{
-    Case, EffectiveBalanceUpdates, Eth1DataReset, HistoricalRootsUpdate, InactivityUpdates,
-    JustificationAndFinalization, ParticipationFlagUpdates, ParticipationRecordUpdates,
-    RandaoMixesReset, RegistryUpdates, RewardsAndPenalties, Slashings, SlashingsReset,
-    SyncCommitteeUpdates,
+    Case, EffectiveBalanceUpdates, Eth1DataReset, HistoricalRootsUpdate, HistoricalSummariesUpdate,
+    InactivityUpdates, JustificationAndFinalization, ParticipationFlagUpdates,
+    ParticipationRecordUpdates, RandaoMixesReset, RegistryUpdates, RewardsAndPenalties, Slashings,
+    SlashingsReset, SyncCommitteeUpdates,
 };
 pub use decode::log_file_access;
 pub use error::Error;
diff --git a/testing/ef_tests/src/type_name.rs b/testing/ef_tests/src/type_name.rs
index bee2d9b03d..0239293e09 100644
--- a/testing/ef_tests/src/type_name.rs
+++ b/testing/ef_tests/src/type_name.rs
@@ -1,4 +1,5 @@
 //! Mapping from types to canonical string identifiers used in testing.
+use types::historical_summary::HistoricalSummary;
 use types::*;
 
 pub trait TypeName {
@@ -87,3 +88,4 @@ type_name!(VoluntaryExit);
 type_name!(Withdrawal);
 type_name!(BlsToExecutionChange, "BLSToExecutionChange");
 type_name!(SignedBlsToExecutionChange, "SignedBLSToExecutionChange");
+type_name!(HistoricalSummary);
diff --git a/testing/ef_tests/tests/tests.rs b/testing/ef_tests/tests/tests.rs
index f84be64dad..8a7209b89b 100644
--- a/testing/ef_tests/tests/tests.rs
+++ b/testing/ef_tests/tests/tests.rs
@@ -215,6 +215,7 @@ macro_rules! ssz_static_test_no_run {
 #[cfg(feature = "fake_crypto")]
 mod ssz_static {
     use ef_tests::{Handler, SszStaticHandler, SszStaticTHCHandler, SszStaticWithSpecHandler};
+    use types::historical_summary::HistoricalSummary;
     use types::*;
 
     ssz_static_test!(aggregate_and_proof, AggregateAndProof<_>);
@@ -357,6 +358,12 @@ mod ssz_static {
         SszStaticHandler::<SignedBlsToExecutionChange, MinimalEthSpec>::capella_only().run();
         SszStaticHandler::<SignedBlsToExecutionChange, MainnetEthSpec>::capella_only().run();
     }
+
+    #[test]
+    fn historical_summary() {
+        SszStaticHandler::<HistoricalSummary, MinimalEthSpec>::capella_only().run();
+        SszStaticHandler::<HistoricalSummary, MainnetEthSpec>::capella_only().run();
+    }
 }
 
 #[test]
@@ -423,6 +430,12 @@ fn epoch_processing_historical_roots_update() {
     EpochProcessingHandler::<MainnetEthSpec, HistoricalRootsUpdate>::default().run();
 }
 
+#[test]
+fn epoch_processing_historical_summaries_update() {
+    EpochProcessingHandler::<MinimalEthSpec, HistoricalSummariesUpdate>::default().run();
+    EpochProcessingHandler::<MainnetEthSpec, HistoricalSummariesUpdate>::default().run();
+}
+
 #[test]
 fn epoch_processing_participation_record_updates() {
     EpochProcessingHandler::<MinimalEthSpec, ParticipationRecordUpdates>::default().run();