Geoffrey FitzClarence, 3rd Earl of Munster brother Aubrey. Geoffrey FitzClarence, 3rd Earl of Munster Geoffrey George Gordon FitzClarence, 3rd Earl of Munster, DSO (18 July 1859 – 2 February 1902), known as Lord Tewkesbury 1870–1901, was a British peer, and the great-grandson of King William IV by his mistress Dorothea Jordan. Born Geoffrey George Gordon FitzClarence, he was the son of William FitzClarence, 2nd Earl of Munster (19 May 1824 – 30 April 1901) and Wilhelmina Kennedy-Erskine (27 June 1830 – 9 October 1906). His parents were first cousins, thus making Geoffrey a great-grandson of William IV twice over. His grandfather on his paternal side was
Dorothea of Anhalt-Zerbst Dorothea thus became the ancestress of the "New House of Brunswick", which became extinct in 1873. The family tree of the Duchess, as of 1617, can still be found in the library in Wolfenbüttel. From her marriage with Augustus, Dorothy had the following children: Dorothea of Anhalt-Zerbst Dorothea von Anhalt-Zerbst (25 September 1607, Zerbst – 26 September 1634, Hitzacker) was a member of the House of Askanier and a princess of Anhalt-Zerbst and by marriage Duchess of Brunswick-Wolfenbüttel. Dorothea was the daughter of Prince Rudolf of Anhalt-Zerbst (1576–1621) from his first marriage to Dorothea Hedwig (1587–1609), daughter of the Duke