César is one of the greatest French sculptors of the post-war period, whose creative period is closely identified with that of the Trente Glorieuses. In 1954, he developed welded irons; in 1959, what Pierre Restany called the "creative gesture" with compressions; then came impressions, including variations on the thumb, his thumb, the thumb of a sculptor who had never modelled - humour and derision - in all materials and all dimensions. Later, at the end of the 1960s, he will be interested on expansions and casts, and finally, in 1971, the extremely rare envelopments. From then on, variations, developments and returns to these periods would make this artist, "guided by the logic of the material", one of the most important of his generation.

It was in 1952, on the advice of friends, that César learnt to weld and began to create shapes made from materials salvaged from breakers' yards, enabling him to continue creating for next to nothing at a time when he was in a difficult financial situation.