Peter II, (born April 26, 1648, Lisbon—died Dec. 9, 1706, Lisbon), king of Portugal whose reign as prince regent (1668–83) and as king (1683–1706) was marked by the consolidation of royal absolutism and the reduction of the significance of the Cortes (National Assembly); at the same time he encouraged economic development and guided his nation through a troubled period in Europe.
After the death of his father, John IV, in 1656, Peter’s feebleminded and profligate elder brother Afonso VI brought Portugal to a very low condition. In November 1667 Afonso was sent into confinement in the Azores, and Peter became regent. Shortly thereafter, his brother’s marriage (1666) to Marie Françoise Elisabeth of Savoy-Nemours was annulled, and Peter married her. He quickly made peace with Spain (Feb. 13, 1668), forgoing advantages that might have been expected from the Portuguese victories of 1663–65. When Afonso died on Sept. 12, 1683, Peter became king.
In the last years of the 17th century, the goldfields of Brazil provided Peter with great wealth and enabled him to govern without seeking revenue from the Cortes, which was not convoked after 1697. To stimulate Portuguese industry and commerce, Peter concluded the Methuen Treaty (1703) with England, which agreed to reduce customs duties on Portuguese wines in return for favourable treatment of English woollen goods. The treaty largely resulted from Peter’s having finally adhered (May 1703) to the Anglo-Austrian side in the War of the Spanish Succession, though at first he had allied himself with France. Peter died in the midst of the war, leaving his throne to John V, his son by his second wife, Maria Sophia of Palatinate-Neuburg, whom he had married in 1687, four years after the death of his first wife.