Guaraní forces living in the Jesuit reductions defeat bandeirantes loyal to the Portuguese Empire at the Battle of Mbororé in present-day Panambí, Argentina.

The Guarani are a group of culturally-related Indigenous peoples of South America. They are distinguished from the related Tupi by their use of the Guarani language. The traditional range of the Guarani people is in what is now Paraguay between the Paraná River and lower Paraguay River, the Misiones Province of Argentina, southern Brazil once as far east as Rio de Janeiro, and parts of Uruguay and Bolivia.