In 1889 , Alexander Duff , 6th Earl Fife married Princess Louise of Wales , a daughter of the future Edward VII , and was duly made Duke of Fife , with the usual restrictions on the female line .
That only males could inherit .
In 1889 , Alexander Duff , 6th Earl Fife married Princess Louise of Wales , a daughter of the future Edward VII , and was duly made Duke of Fife , with the usual restrictions on the female line , meaning that only males could inherit .