diff --git a/CHANGES.md b/CHANGES.md
index 010424e07..f393a956b 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,66 @@
+# Synapse 1.100.0rc1 (2024-01-23)
+
+### Features
+
+- Advertise experimental support for [MSC4028](https://github.com/matrix-org/matrix-spec-proposals/pull/4028) through `/_matrix/clients/versions` if enabled. Contributed by @hanadi92. ([\#16787](https://github.com/element-hq/synapse/issues/16787))
+
+### Bugfixes
+
+- Handle wildcard type filters properly for room messages endpoint. Contributed by Mo Balaa. ([\#14984](https://github.com/element-hq/synapse/issues/14984))
+
+### Improved Documentation
+
+- Add a link to the "Request log format" explainer on the "Logging sample config" documentation page. ([\#16778](https://github.com/element-hq/synapse/issues/16778))
+- Fix broken links in issue templates and documentation. ([\#16810](https://github.com/element-hq/synapse/issues/16810))
+- NGINX listen http2 deprecation in documentation template for reverse proxy. ([\#16831](https://github.com/element-hq/synapse/issues/16831))
+
+### Internal Changes
+
+- Faster partial join to room with complex auth graph. ([\#7](https://github.com/element-hq/synapse/issues/7))
+- Improve DB performance of calculating badge counts for push. ([\#16756](https://github.com/element-hq/synapse/issues/16756))
+- Split up deleting devices into batches. ([\#16766](https://github.com/element-hq/synapse/issues/16766))
+- Remove CI check for sign-off as we require a CLA signature instead. ([\#16776](https://github.com/element-hq/synapse/issues/16776))
+- Ensure CI fails when linting fails to make sure auto-merge does the correct thing. ([\#16781](https://github.com/element-hq/synapse/issues/16781))
+- Faster load recents for sync by reducing amount of state pulled out. ([\#16783](https://github.com/element-hq/synapse/issues/16783))
+- Reduce amount of state pulled out when querying federation hierachy. ([\#16785](https://github.com/element-hq/synapse/issues/16785))
+- Pull less state out of the DB when we retry fetching old events during backfill. ([\#16788](https://github.com/element-hq/synapse/issues/16788))
+- Optimize query for fetching to-device messages in `/sync`. ([\#16805](https://github.com/element-hq/synapse/issues/16805))
+- Reject OIDC config when `client_secret` isn't specified, but the auth method requires one. ([\#16806](https://github.com/element-hq/synapse/issues/16806))
+- Allow room creation but not publishing to continue if room publication rules are violated when creating
+  a new room. ([\#16811](https://github.com/element-hq/synapse/issues/16811))
+- Bump minimum supported Rust version to 1.61.0. ([\#16818](https://github.com/element-hq/synapse/issues/16818))
+- Fixup copyright lines in file headers after the licensing change. ([\#16820](https://github.com/element-hq/synapse/issues/16820))
+- Add a `--generate-only` option to the internal configuration/launch script for Complement. ([\#16828](https://github.com/element-hq/synapse/issues/16828))
+- Preparatory work for tweaking performance of auth chain lookups. ([\#16833](https://github.com/element-hq/synapse/issues/16833))
+- Speed up e2e device keys queries for bot accounts. ([\#16841](https://github.com/element-hq/synapse/issues/16841))
+
+### Updates to locked dependencies
+
+* Bump actions/cache from 3 to 4. ([\#16832](https://github.com/element-hq/synapse/issues/16832))
+* Bump actions/download-artifact from 3 to 4. ([\#16795](https://github.com/element-hq/synapse/issues/16795))
+* Bump actions/upload-artifact from 3 to 4. ([\#16796](https://github.com/element-hq/synapse/issues/16796))
+* Bump anyhow from 1.0.75 to 1.0.79. ([\#16789](https://github.com/element-hq/synapse/issues/16789))
+* Bump authlib from 1.2.1 to 1.3.0. ([\#16801](https://github.com/element-hq/synapse/issues/16801))
+* Bump dawidd6/action-download-artifact from 2.28.0 to 3.0.0. ([\#16794](https://github.com/element-hq/synapse/issues/16794))
+* Bump immutabledict from 4.0.0 to 4.1.0. ([\#16812](https://github.com/element-hq/synapse/issues/16812))
+* Bump isort from 5.13.1 to 5.13.2. ([\#16835](https://github.com/element-hq/synapse/issues/16835))
+* Bump lxml from 4.9.3 to 5.1.0. ([\#16813](https://github.com/element-hq/synapse/issues/16813))
+* Bump pillow from 10.1.0 to 10.2.0. ([\#16802](https://github.com/element-hq/synapse/issues/16802))
+* Bump pydantic from 2.5.2 to 2.5.3. ([\#16836](https://github.com/element-hq/synapse/issues/16836))
+* Bump pyo3 from 0.20.0 to 0.20.2. ([\#16791](https://github.com/element-hq/synapse/issues/16791))
+* Bump regex from 1.9.6 to 1.10.3. ([\#16837](https://github.com/element-hq/synapse/issues/16837))
+* Bump ruff from 0.1.13 to 0.1.14. ([\#16838](https://github.com/element-hq/synapse/issues/16838))
+* Bump ruff from 0.1.7 to 0.1.13. ([\#16814](https://github.com/element-hq/synapse/issues/16814))
+* Bump sentry-sdk from 1.35.0 to 1.39.1. ([\#16799](https://github.com/element-hq/synapse/issues/16799))
+* Bump serde_json from 1.0.108 to 1.0.111. ([\#16792](https://github.com/element-hq/synapse/issues/16792))
+* Bump service-identity from 23.1.0 to 24.1.0. ([\#16816](https://github.com/element-hq/synapse/issues/16816))
+* Bump types-commonmark from 0.9.2.4 to 0.9.2.20240106. ([\#16797](https://github.com/element-hq/synapse/issues/16797))
+* Bump types-jsonschema from 4.20.0.0 to 4.20.0.20240105. ([\#16800](https://github.com/element-hq/synapse/issues/16800))
+* Bump types-jsonschema from 4.20.0.20240105 to 4.21.0.20240118. ([\#16834](https://github.com/element-hq/synapse/issues/16834))
+* Bump types-netaddr from 0.9.0.1 to 0.10.0.20240106. ([\#16839](https://github.com/element-hq/synapse/issues/16839))
+* Bump typing-extensions from 4.8.0 to 4.9.0. ([\#16815](https://github.com/element-hq/synapse/issues/16815))
+
+
 # Synapse 1.99.0 (2024-01-16)
 
 Synapse 1.99.0 is the first Synapse release under an AGPLv3.0 licence (with CLA to enable Element to sell AGPL
diff --git a/changelog.d/14984.bugfix b/changelog.d/14984.bugfix
deleted file mode 100644
index b694f6d16..000000000
--- a/changelog.d/14984.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Handle wildcard type filters properly for room messages endpoint. Contributed by Mo Balaa.
diff --git a/changelog.d/16756.misc b/changelog.d/16756.misc
deleted file mode 100644
index 200e18fb7..000000000
--- a/changelog.d/16756.misc
+++ /dev/null
@@ -1 +0,0 @@
-Improve DB performance of calculating badge counts for push.
diff --git a/changelog.d/16766.misc b/changelog.d/16766.misc
deleted file mode 100644
index ded77a11c..000000000
--- a/changelog.d/16766.misc
+++ /dev/null
@@ -1 +0,0 @@
-Split up deleting devices into batches.
diff --git a/changelog.d/16776.misc b/changelog.d/16776.misc
deleted file mode 100644
index 1650075a7..000000000
--- a/changelog.d/16776.misc
+++ /dev/null
@@ -1 +0,0 @@
-Remove CI check for sign off as we require an CLA signature instead.
diff --git a/changelog.d/16778.doc b/changelog.d/16778.doc
deleted file mode 100644
index fe3ca0da7..000000000
--- a/changelog.d/16778.doc
+++ /dev/null
@@ -1 +0,0 @@
-Add a link to the "Request log format" explainer on the "Logging sample config" documentation page.
diff --git a/changelog.d/16781.misc b/changelog.d/16781.misc
deleted file mode 100644
index 2f628dc5c..000000000
--- a/changelog.d/16781.misc
+++ /dev/null
@@ -1 +0,0 @@
-Ensure CI fails when linting fails to make sure auto-merge does the correct thing.
diff --git a/changelog.d/16783.misc b/changelog.d/16783.misc
deleted file mode 100644
index 9d3b96ffc..000000000
--- a/changelog.d/16783.misc
+++ /dev/null
@@ -1 +0,0 @@
-Faster load recents for sync by reducing amount of state pulled out.
diff --git a/changelog.d/16785.misc b/changelog.d/16785.misc
deleted file mode 100644
index 4de185c5d..000000000
--- a/changelog.d/16785.misc
+++ /dev/null
@@ -1 +0,0 @@
-Reduce amount of state pulled out when querying federation hierachy.
diff --git a/changelog.d/16787.feature b/changelog.d/16787.feature
deleted file mode 100644
index cd11e3fa5..000000000
--- a/changelog.d/16787.feature
+++ /dev/null
@@ -1 +0,0 @@
-Advertise experimental support for [MSC4028](https://github.com/matrix-org/matrix-spec-proposals/pull/4028) through `/_matrix/clients/versions` if enabled. Contributed by @hanadi92.
\ No newline at end of file
diff --git a/changelog.d/16788.misc b/changelog.d/16788.misc
deleted file mode 100644
index e58a5a7a3..000000000
--- a/changelog.d/16788.misc
+++ /dev/null
@@ -1 +0,0 @@
-Pull less state out of the DB when we retry fetching old events during backfill.
diff --git a/changelog.d/16805.misc b/changelog.d/16805.misc
deleted file mode 100644
index 0b54ab0f7..000000000
--- a/changelog.d/16805.misc
+++ /dev/null
@@ -1 +0,0 @@
-Optimize query for fetching to-device messages in `/sync`.
diff --git a/changelog.d/16806.misc b/changelog.d/16806.misc
deleted file mode 100644
index 623338268..000000000
--- a/changelog.d/16806.misc
+++ /dev/null
@@ -1 +0,0 @@
-Reject OIDC config when `client_secret` isn't specified, but the auth method requires one.
diff --git a/changelog.d/16810.doc b/changelog.d/16810.doc
deleted file mode 100644
index b652f01dc..000000000
--- a/changelog.d/16810.doc
+++ /dev/null
@@ -1 +0,0 @@
-Fix broken links in issue templates and documentation.
diff --git a/changelog.d/16811.misc b/changelog.d/16811.misc
deleted file mode 100644
index f48dd91c8..000000000
--- a/changelog.d/16811.misc
+++ /dev/null
@@ -1,2 +0,0 @@
-Allow room creation but not publishing to continue if room publication rules are violated when creating
-a new room.
\ No newline at end of file
diff --git a/changelog.d/16818.misc b/changelog.d/16818.misc
deleted file mode 100644
index 0a5ed6dcc..000000000
--- a/changelog.d/16818.misc
+++ /dev/null
@@ -1 +0,0 @@
-Bump minimum supported Rust version to 1.61.0.
diff --git a/changelog.d/16820.misc b/changelog.d/16820.misc
deleted file mode 100644
index 4ea3a699f..000000000
--- a/changelog.d/16820.misc
+++ /dev/null
@@ -1 +0,0 @@
-Fixup copyright lines in file headers after the licensing change.
diff --git a/changelog.d/16828.misc b/changelog.d/16828.misc
deleted file mode 100644
index 6425062bb..000000000
--- a/changelog.d/16828.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add a `--generate-only` option to the Complement launcher.
\ No newline at end of file
diff --git a/changelog.d/16831.doc b/changelog.d/16831.doc
deleted file mode 100644
index bf0ef8907..000000000
--- a/changelog.d/16831.doc
+++ /dev/null
@@ -1 +0,0 @@
-NGINX listen http2 deprecation in documentation template for reverse proxy.
diff --git a/changelog.d/16833.misc b/changelog.d/16833.misc
deleted file mode 100644
index 9714c97a7..000000000
--- a/changelog.d/16833.misc
+++ /dev/null
@@ -1 +0,0 @@
-Preparatory work for tweaking performance of auth chain lookups.
diff --git a/changelog.d/16841.misc b/changelog.d/16841.misc
deleted file mode 100644
index 1999b3397..000000000
--- a/changelog.d/16841.misc
+++ /dev/null
@@ -1 +0,0 @@
-Speed up e2e device keys queries for bot accounts.
diff --git a/changelog.d/7.misc b/changelog.d/7.misc
deleted file mode 100644
index 63f1fb77f..000000000
--- a/changelog.d/7.misc
+++ /dev/null
@@ -1 +0,0 @@
-Faster partial join to room with complex auth graph.
diff --git a/debian/changelog b/debian/changelog
index 8f1f7bb4a..ca0e2aec4 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+matrix-synapse-py3 (1.100.0~rc1) stable; urgency=medium
+
+  * New Synapse release 1.100.0rc1.
+
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 23 Jan 2024 14:24:16 +0000
+
 matrix-synapse-py3 (1.99.0) stable; urgency=medium
 
   * Fix copyright file with new licensing
diff --git a/pyproject.toml b/pyproject.toml
index 3424665b6..3bfbb1cc4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -96,7 +96,7 @@ module-name = "synapse.synapse_rust"
 
 [tool.poetry]
 name = "matrix-synapse"
-version = "1.99.0"
+version = "1.100.0rc1"
 description = "Homeserver for the Matrix decentralised comms protocol"
 authors = ["Matrix.org Team and Contributors <packages@matrix.org>"]
 license = "AGPL-3.0-or-later"