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