He was nominated the third Governor-General of Brazil in 1556, succeeding Duarte da Costa, who was Governor-General from 1553 to 1557. The seat of the government was Salvador, in the present-day state of Bahia. The Jesuits were stern and persistent missionaries of the Catholic faith with the aboriginal people, and their pacification of these warrior societies was one of the most important conquests of Member de Sá"s government.
The Jesuits had conflicts with Duarte da Costa, because he supported the plantation owners, who tried to force slavery upon the Indians.
With the help of the Jesuits, Member de Sá was able to convince the Tamoyo Confederation to withdraw their support to the Frenchmen. Member de Sá died on 2 March 1572, in Salvador.