Here is the full list of all 21 Age of Conquest IV achievements.
Casting a vote on a ballot.
Creating a ballot to be voted on by others.
Make a treaty with another culture.
Achievement for playing 24h or more.
Eliminate 1000 enemy units.
Achievement for 10 games won.
First multiplayer game won.
Playing the first multiplayer game.
Win a game playing as Sparta.
Eliminate 100 enemy units.
Being very liked by the AI players.
Win against the Inhuman-AI.
Achievement for a completing the tutorial.
Hold 80% more of all the occupiable territory combined.
Declare war against a much larger nation.
Being very much hated by the AI players.
Achievement for playing 1h or more.
Achievement for a first game won.
Build a watch tower.
Eliminate 10 enemy units.
Hold a fertility festival in one of your settlements.