César was at the forefront of the Nouveau Réalisme movement with his radical compressions (compacted automobiles, discarded metal, or rubbish), expansions (polyurethane foam sculptures), and fantastic representations of animals and insects.

He was a French sculptor, born in 1921 to Italian parents from Tuscany in the working-class neighbourhood of la Belle-de-Mai in Marseilles.

His early work used soldered and welded metal as well as junk materials, and by 1960 César was considered one of France's leading sculptors.

In that year, on a visit to a scrap merchant in search of metal, he saw a hydraulic crushing machine in operation, and decided to experiment with it in his sculpture.

Later the same year he joined the Nouveaux Réalistes (New Realists) - Arman, Klein, Raysse, Tinguely, Pierre Restany and others who found their inspiration in urban life.