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