Which civilian car was the German Schwimmwagen based on?

The German Schwimmwagen was based on the Volkswagen Beetle, more precisely the civilian KdF-Wagen from which the Beetle later evolved. It shared much of the Volkswagen family’s rear-engine mechanical layout, but its amphibious body was substantially redesigned.

Porsche designer Erwin Komenda developed a sealed, boat-shaped body because the ordinary Volkswagen floorpan was not suitable for smooth movement through water. The early Type 128 prototype used the Kübelwagen’s longer wheelbase, but its welded hull proved too weak for rough off-road use. The production Type 166 therefore received a shorter, stronger wheelbase.

On land, the Schwimmwagen used four-wheel drive in selected low gears and reverse, along with portal axles that increased ground clearance. In water, a screw propeller could be lowered from the rear and driven directly from the engine. The front wheels acted as rudders, while paddles could help with maneuvering or reversing.

Production ran mainly from 1941 to 1944, and the Type 166 became the most-produced amphibious car in history.