Rosas' attempt to re-annex Uruguay deserves special mention. The five-year period of Uruguayan independence agreed upon by Argentina and Brazil had come to an end when Rosas came into power. Argentina was free to solicit the incorporation of Uruguay into the Argentine Confederation. Oribe, whom we remember as one of Artigas' lieutenants, had become president of Uruguay after Rivera, and allied himself to Rosas against the Rivera faction, which had the support of the Argentine unitarian exiles. Oribe had to abandon Montevideo, which fell into Rivera's hands only to be besieged by Rosas and Oribe. The war that ensued has been called the Great War. It lasted for eight years, from 1843 to 1851, and the entire burden of the struggle centered around the siege of Montevideo, one of the longest in history. During this long eight-year siege, Montevideo received the help of many adventurers and lovers of liberty, as Rosas and Oribe were regarded as oppressors who sought to dominate a weaker country. Garibaldi, famous in Italian history, played a prominent part in the defense of the beleaguered city as leader of a famous foreign legion composed of Italians and Frenchmen. Eventually Rosas brought about his own downfall. Although a federalist, he slowly centralized all power in himself, thereby gaining the distrust of the other _caudillos_. Urquiza, the _caudillo_ from Entre Ríos, led the revolt against Rosas, and at the battle of Caseros, in 1851, completely routed the forces of the tyrant. Flight was Rosas' only resource, and he took refuge, with his daughter Manuela, on board the English frigate _Centaur_. He ended his days in England. But not yet were discords at an end. The victor of Caseros convened a constituent congress at Santa Fé, to which Buenos Aires failed to send delegates, remaining a sovereign state in the same manner that Rhode Island did when she refused to become a party to the Constitution of the United States. Naturally, Urquiza became president, and the provinces prospered under his administration. Such a situation, however, could not endure for long.