Princess Mary of Great Britain Princess Mary of Great Britain Princess Mary of Great Britain (5 March 1723 – 14 January 1772) was the second-youngest daughter of King George II of Great Britain and his wife Caroline of Ansbach, and Landgravine of Hesse-Kassel as the wife of Landgrave Frederick II. Princess Mary was born at Leicester House, Westminster, London. Her father was the Prince of Wales, later King George II. Her mother was Caroline of Ansbach, daughter of Johann Friedrich, Margrave of Brandenburg-Ansbach. Her father succeeded, as George II, on 11 June 1727, and she became "HRH The Princess Mary". Upon her death in 1737,
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