Louis I, 1838–89, king of Portugal (1861–89), son of Maria II and Ferdinand II. He succeeded to the throne on the death of his brother Peter V. His reign was marked by much political turmoil and by a growth of republicanism, while a succession of alternating liberal and conservative ministries accomplished little. In 1886, Portugal secured French and German recognition of its claim to the African interior between Angola and Mozambique, but this was challenged by Great Britain. Slavery was abolished in the Portuguese colonies during Louis's reign, and Portugal made considerable progress in transportation, commerce, and industry. Louis was succeeded by his son, Charles I.

Louis I, 1786–1868, king of Bavaria (1825–48), son and successor of King Maximilian I. He was chiefly responsible for transforming Munich into one of the handsomest capitals of Europe and for making it a center of the arts. His reign, liberal at first, became reactionary, and his unpopularity was heightened by his liaison with Lola Montez. The Revolution of 1848 forced him to abdicate in favor of his son, Maximilian II.