The Battle of San Nicols was a naval engagement on 2 March 1811 on the Paran River between the Spanish royalists from Montevideo, and the first flotilla created by the revolutionary government of Buenos Aires. It was the first engagement between the two fleets in the Ro de la Plata region since the revolution, and a royalist victory.



The Argentine War of Independence (Spanish: Guerra de Independencia de Argentina) was secessionist civil war that fought from 1810 to 1818 by Argentine patriotic forces under Manuel Belgrano, Juan José Castelli and José de San Martín against royalist forces that fought for preserve the integrity of the Spanish crown. On July 9, 1816, an assembly met in San Miguel de Tucumán, declared the independence with provisions for a national constitution.