Romulus Augustulus said:
Anyway...most Paradox games would count. Hearts of Iron 2, for instance...or Europa Universalis and friends.
Anything by Paradox Entertainment in my book deserves an entry into AH gaming Hall of Fame. I've probably got more playing time out of those games than of many more visually polished ones that just prove that there is more to gameplay than slick interface.
As a matter of fact, some Europa Universalis II players created a scenario they call "Aberration", which is an Alternate History scenario (for years 1419-1819) with a variety of changes, including a surviving somewhat strong Byzantium, Granada-dominated Spain, powerful Ukraine (and no Russia), and the great colonizer nation of Eire (Ireland). For the EUII fans here, it is a highly recommended scenario that builds a well developed AH world, with the events that simulate the development of nations in that ATL, but leave enough space for determination. Last I've heard the people who created "Aberration" are doing a Victoria version of it, set in the same world, but in the era of Victoria (1836-1920).
One can also argue that most strategy games out there that allow the player to be any side in the conflict/competition could potentially be an AH game (see Total War series for example - things rarely develop the way they do in OTL, as I've seen things like Holy Roman Empire-dominated Europe - by 1150, nonetheless!; resurgent Byzantium in 1321 scenario that completely takes out Ottomans by 1350; or, even stranger, the World-Conquering Empire of... yes, Switzerland!).