The bombing of Rome in World War II took place on several occasions in 1943 and 1944, primarily by Allied and to a smaller degree by Axis aircraft, before the city was invaded by the Allies on June 4, 1944. Pope Pius XII was initially unsuccessful in attempting to have Rome declared an open city, through negotiations with President Roosevelt via Archbishop (later Cardinal) Francis Spellman. Rome was eventually declared an open city on August 14, 1943 (a day after the last Allied bombing) by the defending forces.