Here is the full list of all 21 Mount & Blade: With Fire and Sword achievements.
Finish the Moscovite Tsardom's main storyline quest "The False Dmitry"
Complete the summer feast quest found in any village on the eastern side of the map.
Finish the Polish Commonwealth's main storyline quest "The Deluge"
Tend to your army's illnesses, five times, by resting or feeding them.
Join the Crimean Khanate and eliminate all other factions.
Join the Kingdom of Sweden and eliminate all other factions.
You've made 1,000,000 thaler from using trade caravans.
You've made 100,000 thaler from using trade caravans.
Finish the Cossack Hetmanate's main storyline quest "The Black Mace"
As any faction; conquer the map and eliminate all other factions.
Keep 10 bundles of velvet in your inventory.
Earn 3,000 thaler in profit from a single caravan trade.
Customise your mercenaries' equipment using the mercenary camp.
Build three upgrades in a single town/castle you control.
Successfully blow a hole in a castle/town wall before a siege.
Build a wagon fort from the camp menu.
Buy drinks for everyone at a bar.
Kill 50 enemies with grenades.
Start any main storyline quest found in the three main factions.
Using any firearm; kill 100 enemies.
Get in a bar fight.