Manuel I of Portugal
Manuel's mother was the granddaughter of King John I of Portugal, whereas his father was the second surviving son of King Edward of Portugal and the younger brother of King Afonso V of Portugal. In 1495, Manuel succeeded his first cousin, King John II of Portugal, who was also his brother-in-law, as husband to Manuel's sister, Eleanor of Viseu.
Flag of Portugal
John II was succeeded by his first cousin Manuel I, in 1495. This king was the first to convert the traditional square armorial banner into a rectangular (2:3) field with the coat of arms on its centre. Specifically, the flag was now a white rectangle centrally charged with the coat of arms (bearing eleven castles) on an ogival or heater-shaped shield and surmounted by an open royal crown. This flag was used exclusively as the kingdom's banner since Manuel I possessed a personal standard which included the armillary sphere for the first time.