There were no revolutions, but a referendum and political pressure. Thus ended the Italian monarchy. It was June 13, 1946, when Umberto II of Savoy, having reigned for just a month, decided to leave for exile in Portugal. Umberto II was the "May King," ascending the throne on May 9 after the abdication of his father, Victor Emmanuel III, who had been involved with fascism. His role was supposed to save the monarchy, clean it up, and make it acceptable for a country devastated by the war. But time was too short, and the burden of the past was too great.

On June 2 and 3, Italians voted on whether to choose a monarchy or a republic. It was the first universal suffrage election, where women also voted. The results were slow and controversial. Ultimately, the Republic prevailed with approximately 12.7 million votes against the monarchy's 10.7 million, but the margin was not enough to quell suspicions. Monarchists denounced irregularities, demanded verification, and spoke of fraud. In the days following the vote, tensions mounted, and the government led by Alcide De Gasperi pushed for a swift solution. On June 10, the Court of Cassation announced the provisional results and postponed the final proclamation. It was a delicate moment, because the monarchy still existed, but had already been rejected at the polls.
Umberto II reacted with a gesture that smacked of surrender, but also of political choice. On June 12, he issued a proclamation challenging the legitimacy of the transfer of power and denouncing a "revolutionary" decision. However, the next day he left Italy. It was a deliberate exit designed to avoid confrontation. The risk was real because the streets were armed, the army was divided, and the country was still awash with weapons after the civil war. Remaining could mean turning an institutional crisis into open conflict. Leaving, however, means defusing the fuse. At around 3:00 PM on June 13, the royal plane took off from Ciampino Airport, bound for the seaside resort of Cascais, near Lisbon. On board was the king without a kingdom. He would never return to Italy. Meanwhile, in Rome, the government assumed power. De Gasperi became the provisional head of state, and on June 18, the Court of Cassation officially proclaimed the Republic's victory. It was the formal end of the monarchy, but the substantial end had already occurred five days earlier, on a landing strip.