Gabriel Voisin was a major manufacturer of airplanes during World War I. The end of the war saw him with a large fortune and an equally large factory, but a very small market for airplanes. In 1919, he decided to become a car manufacturer and acquired a ready-made engine design–a 3969cc sleeve-valve four which had been considered and turned down by Citroën as unsuitable for mass production. Voisin remained faithful to the sleeve-valve principle for the rest of his career as a car maker. Voisin built lightweight cars using techniques learned in his years as an aircraft designer. The type C28 “ambassade” body design was inspired by the art-deco period and was the last model Voisin was personally responsible for.