The DLC pack, to be released as three episodes, is entitled The Tyranny of King Washington, and appears to be a sort of infinite history, described by Ubisoft as follows:
"It's 1783. As the revolution comes to a close, a new and most unexpected enemy emerges. Driven by the desire to secure the fate of the colonies, George Washington, the greatest hero of the revolution, succumbs to the temptation of infinite power. The new King is born and his reign leaves no one untouched. To return freedom to the land, our new hero Connor must dethrone a tyrant he once called friend."
Ubisoft executive producer Sebastien Puel adds: "While Assassin's Creed III concentrates on history as it happens, we wanted to take some liberties with this DLC and tell you how things 'could have happened."
A DLC Season Pass will be available from launch for 2400 Microsoft Points, or $30.
Assassin's Creed III is set for release on 30th October in North America and 31st October in Europe on PS3, Xbox 360 and PC, with a Wii U release to follow.