The Battle for Fort Amol

Walkthrough
Talk to Legate Rikke in the Eastmarch Imperial Camp to receive the next objective. She will say to go to Fort Amol and assist the soldiers there. Travel to Fort Amol which is located southwest of Windhelm and east of Hillgrund's Tomb. Rendezvous with the Imperial soldiers. Once that is done, the next objective will be to attack the fort. There will be barricades in the entrance of the fort so take those out first to help the imperial soldiers get in. Kill as many Stormcloak soldiers as possible. Once the fort's resistance has reached 0% the quest will be complete.

Trivia

 * When the barricades are destroyed, be sure to let some Imperial soldiers in first before entering the courtyard. Otherwise, the Stormcloak soldiers will all target the Dragonborn.

Bugs

 * When given the task, Imperial soldiers will not appear near the fort, making it impossible to join them. The fort is empty, also making it impossible to take it. This is fixable on the PC by using the console command "setstage CWFortSiegeFort 10" as it spawns the Stormcloaks and Imperials, however note that the Stormcloaks will be hostile to the Dragonborn if the command is used in the Fort itself.
 * When speaking to Legate Rikke the "Reporting for duty." option may not appear. Reboot the game or reload an earlier save file to fix this (confirmation needed). Alternatively, go to Fort Amol and kill the guards, the "Reporting for duty" option should be available (confirmed). PC: It is also possible to re-fast travel to the camp, or just leave to somewhere else and then come back. 360: Using the cooking pot in the camp may also fix the issue (confirmed).
 * When in battle it is possible for the rebels to group up in one large area on the wall making it very difficult to attack them directly but the Imperials do not attack, instead they run into a wall. Dragon shouting them and attacking is a workable strategy.
 * Upon finishing "The Battle for Fort Amol" the quest marker indicates to return to Legate Rikke but she will not give any options and the quest line comes to a standstill. To fix this, head to the Windhelm Stables and walk towards Windhelm, along the way, General Tullius will be seen giving a speech. Once he's finished the quest line advances. (confirmation needed) (can confirm on Xbox 360)
 * After killing all the Stormcloaks in the fort, the Imperials can be killed too, but unlike the other forts, the Imperials will respawn. This is a prime area to collect black souls or to train combat skills since the Imperials will never stop respawning until the area is left. This is also nice because all the Imperials spawn in large groups and are extremely easy to kill. Also if the fort is entered, the combat will stop save a few soldiers that follow in. When the inside of the fort is exited, the Imperials won't fight until provoked but will still continue to respawn allowing for a stop in combat at any time.
 * So many people may spawn at one time inside of the fort during the battle, the whole game will lag out.

Die Schlacht um Festung Amol Битва за форт Амол