You will be given a definition of a task first, then some input of the task.
In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.

Context: When the succession war between Ferdinand I and John Zapolya started, he took the side of Zapolya. After the defeat of Zapolya in the Battle of Tokaj in 1527 Link Information: Ferdinand I () (10 March 1503 25 July 1564) was Holy Roman Emperor from 1556, king of Bohemia and Royal Hungary from 1526, and king of Croatia from 1527 until his death in 1564. Answer: 1
Output:
How long had Ferdinand I been in power when he defeated Zapolya?