diff --git a/telegram/bot.py b/telegram/bot.py
index d65a7b6..67f2e75 100644
--- a/telegram/bot.py
+++ b/telegram/bot.py
@@ -268,9 +268,20 @@ def _compress_history(history: list[dict]) -> str:
 
 
 def _format_conversation_history(chat_id: int, user_id: int) -> str:
-    """Format conversation history with compressed context summary (Ganymede: Option C+A)."""
-    key = (chat_id, user_id)
-    history = conversation_history.get(key, [])
+    """Format conversation history with compressed context summary (Ganymede: Option C+A).
+
+    In group chats, merges user-specific history with chat-level history
+    so the bot sees exchanges from other users in the same chat.
+    """
+    user_key = (chat_id, user_id)
+    chat_key = (chat_id, 0)  # chat-level history (all users)
+
+    # Merge: chat-level history gives full group context
+    chat_history = conversation_history.get(chat_key, [])
+    user_history = conversation_history.get(user_key, [])
+
+    # Use chat-level if available (group chats), otherwise user-level (DMs)
+    history = chat_history if chat_history else user_history
     if not history:
         return "(No prior conversation)"
 
@@ -280,8 +291,9 @@ def _format_conversation_history(chat_id: int, user_id: int) -> str:
 
     # Full exchange log for reference
     for exchange in history:
+        who = exchange.get("username", "User")
         if exchange.get("user"):
-            lines.append(f"User: {exchange['user']}")
+            lines.append(f"@{who}: {exchange['user']}")
         if exchange.get("bot"):
             lines.append(f"Rio: {exchange['bot']}")
         lines.append("")
@@ -675,12 +687,21 @@ IMPORTANT: Two special tags you can append at the end of your response (after yo
 
     # Update conversation state: reset window, store history (Ganymede+Rhea)
     if user:
+        username = user.username or "anonymous"
         key = (msg.chat_id, user.id)
         unanswered_count[key] = 0  # reset — conversation alive
+        entry = {"user": text[:500], "bot": response[:500], "username": username}
+        # Per-user history
         history = conversation_history.setdefault(key, [])
-        history.append({"user": text[:500], "bot": response[:500]})
+        history.append(entry)
         if len(history) > MAX_HISTORY:
             history.pop(0)
+        # Chat-level history (group context — all users visible)
+        chat_key = (msg.chat_id, 0)
+        chat_history = conversation_history.setdefault(chat_key, [])
+        chat_history.append(entry)
+        if len(chat_history) > MAX_HISTORY:
+            chat_history.pop(0)
 
     # Record rate limit
     if user: