The name of a Byzantine
emperor and a king of Portugal
Born John Cantacuzene, John VI (1292–1383) was Byzantine emperor from 1347 until 1354. Chief Minister under Andronicus III, John made a play for the throne when Andronicus died, defeating the rightful heir John V with the help of the Ottoman Turks. John VI’s reign was generally peaceful, and saw a temporary decline in civil and religious strife. In 1354, John VI abdicated in favor of John V and retired to a monastery, where he wrote a history of the Empire from 1320 to 1356. A staunch defender of the mystical theory known as Hesychasm, he was instrumental in its acceptance by the Eastern Orthodox Church.
The son of Maria I and Peter III, John VI (1769–1826) was king of Portugal from 1816–1826. John first assumed power in 1792 when his mother became insane, although he did not formally become regent until 1799. John brought Portugal into an informal alliance with England against revolutionary France, causing Portugal to be invaded by the by French and Spanish in 1801. John was quickly defeated and forced to submit completely to Napoleon's authority in the humiliating Treaty of Badajoz (1801). After six years as an effective vassal state of France, Portugal was again invaded by the French on Napoleon's orders in 1807. John and his family fled to Brazil where he set up court as an absentee monarch. The British later liberated Portugal from the French and set up a temporary regency to rule until John's return, but John elected to remain in Brazil, even after his ascension to the Portuguese throne upon his mother's death in 1816. Finally a liberal revolution against the British regency forced John to return to Portugal and reluctantly accept a new liberal constitution, which he sought to undermine for the rest of his reign. In 1824, John put down an absolutist revolt headed by his wife, Queen Carlota Joaquina, and his son Miguel and in 1825 he recognized Brazilian independence. Upon his death John left the regency of Portugal to his daughter Isabel, who recognized John's son Pedro as Peter IV of Portugal.