 In March 1945, during World War II, the U.S. VI Corps and the French First Army assaulted German Siegfried Line fortifications in the Bienwald and penetrated German defenses in the forest during a week of heavy combat.The forest is still marked by trenches and bunker ruins from World War II.There are also older French earthworks ("redoutes") in the southwestern parts of the forest where it borders the Lauter river and Mundat Forest ().