Which historical period is depicted in the first Assassin's Creed game?

The first Assassin's Creed game is set during the Third Crusade.

Its historical storyline takes place in 1191, when Altaïr Ibn-La'Ahad carries out missions in the Levant. The major cities represented in the game are Jerusalem, Acre, and Damascus, all of which are connected to the conflict between Crusader and Saracen forces.

The game uses real historical figures, including Robert de Sablé, William of Montferrat, and Richard the Lionheart, while placing its fictional Assassin characters inside the period's political struggles. The narrative is not a complete history of the Crusade; it is a fictional conspiracy story set against real events and places.

The Third Crusade lasted from 1189 to 1192. It followed the capture of Jerusalem by Saladin in 1187 and included campaigns led by figures such as Richard I of England. The game's 1191 setting falls within that wider conflict.