Assassin's Creed Brotherhood is a 2010 action-adventure video game developed by Ubisoft Montreal and published by Ubisoft. It is the third major installment in the Assassin's Creed series, a direct sequel to 2009's Assassin's Creed II, and the second chapter in the 'Ezio trilogy'. The game was first released on the PlayStation 3 and Xbox 360 in November and December 2010, and was later made available on Microsoft Windows in March and June 2011.

The plot follows the centuries-old struggle between the Assassins, who fight for peace with free will, and the Templars, who desire peace through control. The framing story is set in the 21st century and features series protagonist Desmond Miles who, with the aid of a machine known as the Animus, relives the memories of his ancestors to find a way to avert the 2012 apocalypse. The main story takes place immediately after the plot of Assassin's Creed II, featuring Assassin Ezio Auditore de Firenze in 16th century Italy and his quest to restore the Assassin order, and destroy his enemies: the Borgia family.

Assassin's Creed: Brotherhood is set in an open world and presented from the third-person perspective with a primary focus on using Desmond and Ezio's combat and stealth abilities to eliminate targets and explore the environment. Ezio is able to freely explore 16th-century Rome to complete side missions away from the primary storyline. The game introduced a multiplayer component to the series, portrayed as a Templar training program.

The game received critical acclaim with critics praising its setting of Rome, content, gameplay improvements over its predecessor and the addition of a multiplayer mode; the story received a mostly positive response, although several critics found it to be inferior to Assassin's Creed II's. It also won multiple awards including a BAFTA award for Best Action Game. It was followed in November 2011 by Assassin's Creed: Revelations, a direct sequel that served as a conclusion to Ezio's story and continued the story of Desmond Miles.

A remastered version, along with Assassin's Creed II and Assassin's Creed: Revelations, was released for the PlayStation 4 and Xbox One on November 15, 2016 under the name The Ezio Collection.