Of course the publisher Ubisoft played as a protagonist in E3, announcing new games like Watch Dogs, or showing off a lot of media assets about the well-know upcoming titles, like its action-adventure third-person shooter Assassin's Creed III.
You can look here the "Assassin's Creed III E3 Frontier Gameplay Demo [North America]", a 7 minutes long trailer that presents the gameplay of Assassin's Creed III while Connor, according to Ubisoft, traverses the vast Frontier on a mission to assassinate an enemy who infringes upon his people's freedom and liberty.
Ubisoft added also some details on the story of Assassin's Creed III, a game that brings the player first, during and after the American Revolution. This's the official presentation posted by the publisher: "The American Colonies, 1775. As a Native American Assassin fights to protect his land and his people, he will ignite the flames of a young nation's revolution. In Assassin's Creed III, eliminate your enemies with guns, bows, tomahawks, and more! In development for over three years, the game features the new Ubisoft-AnvilNext engine, a stunning technology that will revolutionize gaming."
Assassin's Creed III is now under development at the Ubisoft Montreal studios: based on AnvilNext graphics engine, the next entry of Assassin's Creed series will be available in four editions for the gaming platforms Microsoft Xbox 360, Sony PlayStation 3 and Wii U by Nintendo starting from October 30th 2012 in North America and one day later in PAL regions, including those european.