The Citroën Traction Avant (1934) was the first mass-production car with a monocoque structure.

In 1935-36 the bodyshop Carrozzeria Touring developed the "Sistema Superleggera" (in English: Superlight System) construction scheme: the frame was made by a mesh of small diameter tubular elements in Chrome-Molibdenum steel welded together. This chassis was then welded to the frame rails. The stamped aluminum sheet body panels were clinched to the tubular chassis and had no structural functionality. The main application was the construction of racing cars, but some luxury production vehicles also adopted thi solution.

Lancia Aprilia structure (1937), with "Touring Superleggera" body and chassis

During the 1940's, the World War II caused most of automotive indutries to be converted into military production, and the automotive technologies had a temporary stop.

After the war, in the USA the Car Manufacturers started to look to "performance" as the main scope of their research, and the weight reduction became of secondary relevance.

In the meantime in Europe the lack of steel pushed the industry towards the development of lighter cars, with a large diffusion of aluminum alloys both for components and car body panels.

Land Rover (1948)

The Land Rover (1948) with its riveted aluminum body was a result of this phenomenon.