Here is the full list of all 17 Buccaneers! achievements.
Conquer the Caribbean for France.
Conquer the Caribbean for Spain.
Conquer the Caribbean for the Buccaneers' League.
Conquer the Caribbean for Britain.
Reach player level 20.
Steal a ship from an enemy harbour.
Complete Act 3.
Fully upgrade a ship.
Acquire a Three-Decker.
Complete Act 2.
Have a full fleet of four ships (excluding temporary ships).
Complete Act1.
Have a fleet of two or more ships (excluding temporary ships).
Choose which faction to join.
Capture any town by defeating its fort.
Rename a ship.
Capture a ship.