User blog comment:Deathmanstratos/Black Ops II Apocalypse DLC announced/@comment-68.44.177.126-20130808195246/@comment-3171236-20130808211732

Treyarch specifically said Origins is set in a "Dieselpunk-stylized" France in World War 1. You fight a 1000 foot tall robot, and you have access to a World War 1 Tank as a Wonder Weapon.

Since one of the blueprints showed a modified Mauser pistol, I wouldn't be surprised if there were some Steampunk-styled World War 1 weapons to use in the map.