The creation of the 3rd district of peace in the Village of Santa Maria began with a decree from the Provincial Government on June 18, 1861.

Its boundaries were nearly identical to the current municipality of São Pedro do Sul, and its first justice of the peace was José Luiz Medeiros.

Until 1926, it belonged to Santa Maria, and on March 22, 1926, it gained its political/administrative independence through State Decree No.

[2] The municipality is located at a latitude of 29º37'14" south and a longitude of 54º10'44" west, at an altitude of 173 meters.

The city of São Pedro do Sul, along with the city of Mata, is part of the Arenito Mata Paleobotanical Sites, created by the Brazilian Commission of Geological and Paleobiological Sites.