The Argentine Confederation (Spanish: Confederación Argentina) is one of the official names of Argentina, according to the Argentine Constitution, Article 35. It was the name of the country from 1831 to 1852, when the provinces organized themselves as a confederation, without a head of state. The governor of Buenos Aires Province (Juan Manuel de Rosas during most of the period) managed the foreign relations during the time. Under his rule, the Argentine Confederation resisted wars from Bolivia, Uruguay, France and Britain, as well as attacks of other Argentine factions during the Argentine Civil Wars.
Rosas was ousted from power in 1852 by Justo José de Urquiza, after the battle of Caseros. Urquiza convened the 1853 Constituent Assembly to write a national constitution. Buenos Aires resisted Urquiza and seceded from the Confederation in 1852, becoming the State of Buenos Aires; the province would return to Argentina in 1861.