The opening historical setting of the first Assassin's Creed game is the year 1191.
The game takes place during the Third Crusade, a period of conflict involving European crusaders, Muslim forces, and competing political powers in the eastern Mediterranean. Altaïr Ibn-La'Ahad carries out missions in cities including Masyaf, Acre, Damascus, and Jerusalem during this setting.
The year 1191 places the story near the end of the Third Crusade. Historical figures such as Richard the Lionheart appear alongside fictional characters and secret organizations. The game uses real medieval locations and political tensions, while its central struggle between Assassins and Templars is presented as fictional secret history.
This date is sometimes confused with 1099, the year Jerusalem was captured during the First Crusade, or 1453, the year Constantinople fell to the Ottoman Empire. Neither is the opening year of the first game. Assassin's Creed was released in 2007, but its historical narrative begins centuries earlier, in 1191.