diff --git a/CHANGELOG.md b/CHANGELOG.md
index 58344cc5b..a085ebf82 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,9 @@ Format based on [Keep a Changelog](https://keepachangelog.com/).
 
 ## [Unreleased]
 
+### Changed
+- Replaced all in-universe "Commonwealth" references with "the Settled Reach" across 44 files (agents, decisions, docs, tooling, server). Historical discussion transcripts and Hamilton book references kept as-is.
+
 ### Added
 - Triangle activation proximity monologue lines — 5 smuggler lines (Kael Davan) and 5 detective lines (Sera Venn/Torek Lintar) that fire when observing triangle anchor NPCs post-activation (#597, D-035, D-039)