(Note: I just realized I posted to the wrong thread but don't know how to move/delete this!
Should be in Civ 4 > Strategy and Tips)

Level: Nobel

In some games when I declare war against the AI, the AI's city will be defended by several units (often archers) with either City Garrison II or City Garrison III promotions. Since this is usually early in the game and no other civ is on the continent, how is the AI able to get promotions at that level before anything has happened?

I can understand Combat II or Combat III promotions since that can happen by encountering barbarians, but the higher defensive ones puzzle me (since I've never had the opportunity to get City Garrison III yet in all my playing!).

Thanks for any insight.