Renato Casaro was born on 26 October 1935 in Treviso.[3] His early interest in posters reportedly began with movie advertisements. He would go every day to the cinema to see if they were changing the posters, and if they were he would ask if he could take them home where he would try to reproduce them.[4] In 1953, at age 18, Renato found a job as a staff artist at Studio Favalli, a famous design and art studio of Rome's film industry. In Rome, at age 21, Renato opened his own art studio.[5]
In 2019, Casaro was called by Quentin Tarantino to realize some "old school illustrated Western posters" ("Uccidimi Subito Ringo, disse il Gringo" aka "Kill Me Now Ringo, Said The Gringo" and "Nebraska Jim") for Italian films starring Rick Dalton, the character Leonardo DiCaprio plays in Once Upon a Time in Hollywood.[7][8]