Although the true beginning of neorealism has been widely contested by theorists and filmmakers, the first neorealist film is generally thought to be Visconti's Ossessione, released in 1943, during the occupation. Neorealism became famous globally in 1946 with Roberto Rossellini's Rome, Open City, when it won the Grand Prize at the Cannes Film Festival as the first major film produced in Italy after the war.