How did Philip's wife become the heiress to the Castilian throne?
Won a battle
Inherited it
Marriage
Elected
Answer
The claim to the Castilian throne came through Philip's wife, Joanna, known as "Joanna la Loca" (Joanna the Mad). Joanna was the daughter of the Catholic Monarchs, Ferdinand and Isabella, who ruled Spain jointly. As their only surviving child, Joanna was next in line to the throne.
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