Here is the full list of all 35 Age of Civilizations II achievements.
Create 50 unions
Join 50 alliances
Create 25 unions
Join 25 alliances
Create 10 unions
Create 5 unions
Create 50 vassals
Create 20 vassals
Create 5 vassals
Form Italy
Form Japan
Join 10 alliances
Form Austrian Empire
Capture 1500 provinces
Form Russian Empire
Create a vassal
Join 5 alliances
Adopt the Monarchy government
Adopt the ideology of Communism
Adopt Fascism ideology
Adopt the ideology of the City State
Adopt the Horde ideology
Form Ottoman Empire
Capture 750 provinces
Adopt Republic ideology
Form Australia-Hungary
Capture 500 provinces
Adopt the ideology of democracy
Capture 300 provinces
Create union
Join alliance
Capture 150 provinces
Capture 75 provinces
Capture 30 provinces
Capture 10 provinces