ANSWER When the Emperor Charles V of Hapsburg became also King Charles I of Spain in 1516
Charles I was the King of Spain from 1516 until his death in 1556.
In 1516, Charles V became the King of Spain. Spain ended up becoming more firmly enmeshed with the dynastic struggles of Europe.
Ferdinand ll was king of Spain in 1514. Ferdinand was king from 1479 until 1516. He was known as Ferdinand of Aragon.
King Ferdinand II died on June 23, 1516 in Madrigalejo, Spain for an unspecified reason.
From 1516 to 1556 the King of Spain was Charles I. There was no Queen of Spain until Charles I married his cousin Isabella of Portugal in 1526.
The King of Spain in 1525 was King Ferdinand who ruled from 1516 to 1555. His wife was his first cousin who he married in 1525 and her name was Isabella.
Charles I was the first King of Spain. He inherited the Kingdoms of Castile, Leon, and Aragon in 1516. His Queen was Isabella of Portugal.
Philip II of Spain was King of Spain from 1556 until 1598
King Ferdinand II died in 1516. He was King of Sicily until he married Queen Isabella. Then he became King of Castile.
Carlos I was the very first monarch of a united Spain. He was also known as Charles V Holy Roman Emperor.
The King of Spain in 1552 was Charles I. Charles I ruled Spain from 1516 to 1556. He gave up some of the territory owned by Spain to his son Philip II in 1552. And then made his brother, Ferdinand, King of Spain the same year. This split the Netherlands away from Spain's rule.