The lack of a male heir following six years of marriage could also be one of the reasons.

Because of the lack of an heir, the town fell back to the emperor in 1556.

Some acceded to the throne in their own right due to the lack of a male heir.

However, by the end of the 16th century, the elder branch of the family died out for lack of a male heir.

His lack of an heir alone would disqualify him.

He was adopted due to a lack of an heir to the Uchida fmaily name.

We're all a bit nervous about the lack of an heir to the throne.

The lack of a clear heir led to a period known as the 'Great Cause', with several families laying claim to the throne.

However, he had never married, and the title became extinct on his death for lack of an heir.

A third problem derived from the lack of a direct heir to the throne.