John, Prince of Asturias

John, Prince of Asturias, (Seville, 28 June 1478 4 October 1497) was the only son of Isabella I of Castile and Ferdinand II of Aragon who survived to adulthood. Isabella and Ferdinand, together with their cousin, Duke Francis II of Brittany, planned the alliance of their respective heirs, John and Anne, but didn't eventually pursue this project, perhaps because of John's poor constitution. At the age of 18 John married Archduchess Margaret of Austria (1480-1530) in the Cathedral of Burgos in April, 1497. Six months later, on the way to the wedding of his older sister in Portugal, he died in Salamanca, possibly from tuberculosis. His wife was left pregnant and later gave birth to a stillborn child. John's death, followed closely by those of his elder sister Isabella and her only child led to the inheritance of the Spanish kingdoms by the Habsburgs, descendants of his younger sister Joanna, who had married the Archduchess Margaret's brother, Philip the Handsome. In 1492, Columbus named the newly discovered island of Cuba Isla Juana in deference to Prince Juan, at that time the heir apparent.