The Riograndense Republic, often called Piratini Republic (Portuguese: República Rio-Grandense or República do Piratini), was a de facto state that existed between September 11, 1836 and March 1, 1845 roughly coinciding with the present state of Rio Grande do Sul, in Brazil. Although never recognised as a self-governing state, it voted itself a Constitution in 1843. It was recognized only by Uruguay and Britain. Independence was proclaimed by Antônio de Souza Neto, who assigned Bento Gonçalves da Silva as its first president during the rebellion which became the Ragamuffin War.