Here is the full list of all 68 Tannenberg achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Win 10 matches as the Entente Powers.
Win 25 Gold Medals.
Win 10 games as the Central Powers.
Cut off at least 3 enemy sectors.
Playing as the K.u.K, lose a battle in the Carpathians.
Using a sword, kill an opponent who is also using a sword.
Win a game with a points difference of 100 or less.
Kill 25 enemies with artillery as the Central Powers.
Get 50 artillery kills using trench phones.
Used voice commands 50 times.
Kill 25 enemies with artillery as the Entente Powers.
Die from falling down.
As Frontovik, while crouched, get 3 grenade kills.
Unlock all specializations for the Latvians.
Become cut-off in a sector.
Unlock all specializations for the K.u.K. Trupp.
Unlock all specializations for the Infanterie.
Get 10 kills with swords.
Kill 3 people with a sabre in an enemy held capture zone.
Unlock all specializations for the Cossacks.
Be part of the top scoring squad in a match.
Fight in every weather condition.
Playing as the Entente Powers, capture the enemy HQ.
Complete a match on a snowy map.
Complete a match on a night map.
Playing as the Infanterie, win a battle in East Prussia.
Playing as the Central Powers, capture the enemy HQ.
Visit every sector in a Maneuver match.
Capture 10 enemy sectors.
Switch to other team when asked for autobalance.
Club someone to death with binoculars.
Be the first to get killed by an enemy in a game.
Perform a role switch.
Make a successful retreat
Get a kill from 150m.
Get killed by bots 50 times.
Unlock all specializations for the Frontovik.
Kill 4 enemies with a single grenade or call in.
Make 5 kills within the first two minutes of the match.
Complete a match on a foggy map.
Have your entire squad agree on a vote to change the squad name or type.
Chop off someone's limbs with a sword.
Unlock all specializations for the Roumanians
Check out the credits screen.
Kill an enemy soldier manning a heavy machine gun with a head shot.
Die 10 seconds after spawning.
Get killed by your own grenade.
Unlock all specializations for the Bulgarians
Exhaust all your revolver ammo without missing a shot.
Kill an enemy while shooting through an object.
Get the first kill in a match.
Start a private match.
Kill 25 enemies with a HMG.
Damage two enemies with one bullet.
Kill 10 people with a heavy machine gun in a single life.
Get 7 squad spawns on a single life as NCO.
Resupply your ammo.
Kill 4+ enemies in a capture zone.
Call in Artillery or Recon from a sector.
Have a look at the overview map.
In a single life, take damage from melee attacks and gun shots from a player or players, before being killed by someone entirely different.
Capture an enemy sector alongside 10 or more other people.
Kill 5 NCO's in a match.
Get a kill while injured.
Shoot an enemy while being suppressed or shaken by artillery.
Issue 10 command orders.
Used voice chat.
Kick a bot off of a heavy machine gun.