 In the postwar years , Porto Alegre turned his attention to politics , retiring from his military career as a lieutenant general , the second @-@ highest rank in the Imperial army . He was an affiliate of the Liberal Party at the national level and was elected to the legislature of Rio Grande do Sul . He also founded a provincial party , the Progressive @-@ Liberal Party — a coalition of Liberals like him and some members of the Conservative Party . Porto Alegre later entered the lower house of the Brazilian parliament and was briefly Minister of War . When the Paraguayan War erupted in 1864 , he returned to active duty . One of the main Brazilian commanders during the conflict , his participation was marked by important battlefield victories , as well as constant quarrels with his Argentine and Uruguayan allies . 
