The Society of Jesus, a religious order founded by Ignatius de Loyola in 1539, is another of Rome's strongest weapons in the Counter-Reformation.

The order is dedicated to furthering the cause of Catholicism and propagating its teachings in missions among nonbelievers.

In 1540 three of Loyola's followers—Simão Rodrigues, who is Portuguese; Paulo Camerte, who is Italian; and Francisco Xavier, who is Spanish—arrive in Portugal.

Simão Rodrigues becomes the tutor of the king's son and later founds Jesuit schools at Coimbra and Évora.

By 1555 the Jesuits have control of all secondary education in the realm and by 1558 have established a university in Évora.