The history of Piratini goes back to 1777, when the first portuguese militaries were installed by the riverside of Piratinim, the river from the region. In 1789, 48 couples came from the Azores islands to, in those lands, live and work. Between 1819 and 1824 the most relevant constructions were built.
The warrior tradition of the city began in 1827, when many inhabitants from the community sided in the Cisplatina campaign. With the Farroupilha (Ragamuffins) Revolution, on 8th october 1835, the community was occupied by the Farrapos forces (ragamuffins forces). Due to the strategical position of the city and to the sympathy with which the dwellers received the insurgents, Piratini has been chosen as Center of the operations.
Within less than one year, on 11th september 1836, the Rio-Grandense Republic was proclaimed and Bento Gonçalves da Silva was elected president, even though imprisoned. On 10th november of the same year Piratini was elected the capital of the new Republic and, on 1837, was promoted from village to city. The population has never abandoned the republican principles, joining the battles for the cause.