Which Assassin's Creed game introduced playable naval battles as a major feature?

Assassin's Creed III introduced playable naval battles as a major feature in the series.

Released in 2012, Assassin's Creed III lets players command the Aquila, a sailing warship associated with Connor. Naval missions involve steering, managing speed, positioning the ship, and firing broadside cannons against enemy vessels. The system became one of the game's most distinctive additions.

The main story takes place during the American Revolution, across cities such as Boston and New York as well as a large wilderness area. Naval missions are separate from much of the urban parkour gameplay, giving the game two different styles of historical adventure.

Black Flag later expanded sailing into a much larger open-world system, which causes some players to remember it as the franchise's first naval game. However, Assassin's Creed III introduced the feature first. The earlier games included water and limited ship-related scenes, but not the same dedicated playable naval combat missions.