Wolfenstein is a series of World War II video games, originally developed by Muse Software. The first two games in the series, Castle Wolfenstein and Beyond Castle Wolfenstein, were stealth-based and featured a 2D top-down perspective. The third game in the franchise, Wolfenstein 3D, developed by id Software, introduced a first-person perspective with faster-paced action. Because of this, it is widely regarded to have helped popularize the first-person shooter genre.

In 2001, the series was rebooted with Return to Castle Wolfenstein, developed by Gray Matter Interactive. It was then followed in 2003 by Wolfenstein Enemy Territory, by Splash Damage. Raven Software's Wolfenstein followed in 2009. After Bethesda Softworks acquired id Software, MachineGames released Wolfenstein The New Order in 2014 and a standalone expansion Wolfenstein The Old Blood in 2015. A direct sequel to The New Order entitled Wolfenstein II The New Colossus was released on October 27, 2017.

The majority of the games follow protagonist William "B.J." Blazkowicz, and his fights against the Nazi powers. Earlier titles are centered around Nazis attempting to harness supernatural and occult forces. The New Order and its sequel The New Colossus are set in an alternate history in which the Axis powers won the Second World War.