Uruguayan Civil War: Argentina backs Oribe and the siege of Montevideo begins

Background. The Uruguayan Civil War, known as the Guerra Grande, involved armed conflicts between leaders of Uruguayan independence. Supporters of presidents Rivera and Oribe formed the Colorado and National Parties, receiving foreign backing from Brazil, the Argentine Confederation, and European powers. Oribe, a supporter of Rosas, was forced to resign in 1838 but started a rebel army, leading to a long civil war that lasted until 1851.

Political Context. Manuel Oribe was elected President of Uruguay in 1835, while Fructuoso Rivera remained army commander. Rivera rebelled against Oribe in 1836. Oribe was a big supporter of Juan Manuel de Rosas in Argentina, who in turn supported him. The conflict saw the establishment of two rival governments: the Gobierno de la Defensa in Montevideo and the Gobierno del Cerrito, ruling the rest of the country.

Military Campaign. The second stage of the war, lasting from 1842 to 1851, took place within Uruguayan territory. After the victory at the Battle of Arroyo Grande in December 1842, Oribe's army crossed the Uruguay River and began the siege of Montevideo. The siege lasted for eight years, with Montevideo's population being highly cosmopolitan, with Uruguayans making up only a third of it.