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
Frederick I, Margrave of Brandenburg-Ansbach denied entry to Plassenburg Castle. The dispute was finally cleared when an agreement was reached in 1522, in which the demands of the younger sons of Frederick were met. On 14 February 1479, at Frankfurt (Oder), Frederick I was married to Princess Sophia of Poland (6 April 1464 – 5 October 1512), daughter of King Casimir IV of Poland by his wife Elisabeth of Austria, and sister of King Sigismund I of Poland. They had seventeen children: Frederick I, Margrave of Brandenburg-Ansbach Frederick I of Ansbach and Bayreuth (also known as Frederick V; or ; 8 May 1460 – 4