On 4 April 1860, the latest revolt against the Bourbon regime broke out. Giuseppe Garibaldi, funded and directed by the Piedmontese prime minister Cavour, assisted the revolt with his forces, launching the so-called Expedition of the Thousand. He arrived at Marsala on 11 May 1860 with ca. 1,000 Redshirts. Garibaldi announced that he was assuming dictatorship over Sicily in the name of King Victor Emmanuel II of Sardinia. On 15 May, the Redshirts fought the Battle of Calatafimi and within weeks Palermo was freed from the troops of general Lanza, who even being superior in number, inexplicably retreated. Francis II of the Two Sicilies tried to regain control of the Kingdom. On 25 June 1860, he restored the constitution of the Kingdom, adopted the Italian tricolour as the national flag, and promised special institutions for the Kingdom.