Here is the full list of all 31 Windward achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
Unlock all ships.
Equip an item that will push any stat above 1000.
Sink another player in PvP.
Defeat two enemies back to back.
Defeat an enemy by yourself without taking any damage.
Defeat 100 ships.
Sink a pirate captain in a level 39+ region.
Hire a follower.
Repair your ship while obscured by fog.
Drop Grogolov on top of 3 or more enemies.
Capture a level 9 or higher region in a co-op match.
Completely drive out pirates from a level 9+ region.
Complete 50 commissions.
Establish a foothold in a region where your faction has no towns.
Find and equip your first epic item.
Make a town grow in size.
Do your first trade run.
Defeat a Pirate Captain.
Successfully complete a commission to place a Guard Tower near a town.
Complete two consignments at the same time.
Upgrade your ship.
Achieve a skull kill rating.
Open a Sealed Letter.
Defeat 5 pirates.
Customize your ship's look.
Complete your first commission.
Become a true pirate. Arrr!
Opt out of a PvP match by using a White Flag.
Drive out pirates from a level 39+ region.
Achieve the Admiral reputation standing with any faction.
Complete the Strange Diagram quest.