In 1844, the Emperor appointed Aureliano Coutinho President (governor) of Rio de Janeiro province, the richest and most important province in Brazil.[22][23] With Aureliano Coutinho's patronage and strong political power base, Paranhos was elected in 1845, at age 26, to the Provincial Legislative Assembly—the provincial house of representatives. The following year, Aureliano Coutinho appointed him to be the provincial secretary, then vice-president, and later acting president.[16] In 1847, Paranhos was elected as a general deputy, representing Rio de Janeiro in the national Chamber of Deputies.[24]