Vargas was born on 25 November 1844 in Passo Fundo in the province of Rio Grande do Sul, in the Empire of Brazil. He was one of fourteen children born to Luísa Maria Teresa Vargas, from Rio Pardo, and Evaristo José Vargas, from Encruzilhada. His father fought in the Ragamuffin War as a volunteer soldier of the Riograndense Republic.