Princess and Landgravine Marie of Hesse-Kassel, second daughter of Landgrave Frederick of Hesse-Kassel, and his wife, Princess Caroline of Nassau-Usingen, was born at Hanau, Hesse-Kassel. Through her father, she was a great-granddaughter of George II of Great Britain.
Her father"s older brother was the Landgrave of Hesse-Kassel. In 1803, her uncle"s title was raised to Elector of Hesse — whereby the entire Kassel branch of the Hesse dynasty gained an upward notch in hierarchy. Her sister Augusta married to Prince Adolphus, Duke of Cambridge, the seventh son of George III of the United Kingdom.
Titles and styles 21 January 1796 – 12 August 1817: Her Serene Highness Princess Marie of Hesse 12 August 1817 – 6 September 1860: Her Royal Highness The Grand Duchess of Mecklenburg-Strelitz 6 September 1860 – 30 December 1880: Her Royal Highness The Dowager Grand Duchess of Mecklenburg-Strelitz.
