What was the length of the reign of Umberto II as King of Italy?

Umberto II (Italian: Umberto Nicola Tommaso Giovanni Maria di Savoia; 15 September 1904, Racconigi, Italy – 18 March 1983, Geneva, Switzerland) was a prince of the ruling House of Savoy and briefly, the last King of Italy. Umberto was married in Rome on 8 January 1930 to Princess Marie José of Belgium (1906–2001). They had four children: Maria Pia, Vittorio Emanuele, Maria Gabriella and Maria Beatrice.

Umberto was the son of King Vittorio Emanuele III, who accepted a Liberal cabinet and acquiesced in Italy’s war against Turkey in 1911 and its entrance into WWI in 1915. When the strains put on the parliamentary system by the war brought Mussolini to the fore, Vittorio Emanuele failed to prevent the Fascist seizure of power. He was quickly reduced to a figurehead by Mussolini. On 2 June 1944, after the Allied liberation of Rome, he named his son Crown Prince Umberto, lieutenant-general of the realm, relinquishing all power for himself but retaining his title of king. He finally abdicated in favour of Umberto on 9 May 1946.

Umberto II reigned for 34 days, from 9 May 1946 to 12 June 1946, and was nicknamed the “May King” (Italian: “Re di Maggio”). He was forced to abdicate in June 1946 when more than 54% of Italians cast their referendum vote in favour of a republic and the post-war Italian constitution specifically banned the male heirs of the house of Savoy from setting foot on Italian soil.

The Italian parliament voted in July 2002 to remove the ban.