The history of the city begins in June 1758, through a donation that Gomes Freire de Andrade, Count of Bobadela, made to Colonel Thomáz Luiz Osório, giving him land that lay on the banks of the Lagoa dos Patos. In 1763, fleeing the Spanish invasion, many inhabitants of the village Rio Grande sought refuge in the land belonging to Osório. Later, there also came refugees from Colônia do Sacramento, which had been handed over by the Portuguese to the Spanish in 1777.