William Frederick, Margrave of Brandenburg-Ansbach in Unterreichenbach and was succeeded by his son Charles William Frederick, called "The Wild Margrave". William Frederick, Margrave of Brandenburg-Ansbach William Frederick, Margrave of Brandenburg-Ansbach (8 January 1686 – 7 January 1723), was Margrave of the Principality of Brandenburg-Ansbach from 1703 until his death in 1723. He was the younger brother of Caroline of Ansbach and thus brother-in-law of George II of Great Britain. William Frederick was born in Ansbach in 1686 to John Frederick, Margrave of Brandenburg-Ansbach, and his second wife, Eleonore Erdmuthe of Saxe-Eisenach. His two surviving half-brothers, Margraves Christian Albert and George Frederick II, both died unmarried
Principality of Ansbach reunited under Frederick VI, who had become Elector Frederick I of Brandenburg in 1415. Upon Frederick I's death on 21 September 1440, his territories were divided between his sons; John received the principality of Bayreuth (Brandenburg-Kulmbach), Frederick received Brandenburg, and Albert received Ansbach. Thereafter Ansbach was held by cadet branches of the House of Hohenzollern, and its rulers were commonly called Margraves of Brandenburg-Ansbach. On 2 December 1791, the reigning Prince and Margrave of Ansbach, Charles Alexander, who had also succeeded to Bayreuth, sold the sovereignty of his principalities to King Frederick William II of Prussia. The Margrave was middle-aged