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