Under Defeat is a shoot 'em up arcade game by G.rev. It was released for the Sega Dreamcast in March 2006. The game takes place in an alternate reality based on World War II, and, in a controversial twist, players control German-speaking characters (under the banner of "the Empire") with uniforms that resemble those of the Nazi SS, fighting against enemies ("the Union") that speak English and possess weapons patterned after those of both real-life Allied and Axis powers (for example, naval units in Level 2 bear heavy resemblance toward the Imperial Japanese warships). The game was released very late in the life of the Dreamcast, but sold much better than expected, probably because there were no other home ports planned in the foreseeable future.
Players assume control of a helicopter, which can be rotated like a more limited version of the mechanism in Zero Gunner 2. Gameplay is largely very traditional, and bears a strong resemblance to some older Toaplan games, especially Twin Cobra. It uses 3D graphics, and a slightly angled perspective to give the game more depth than most other titles in the genre.
Source: Wikipedia, "Under Defeat", available under the CC-BY-SA License.