Marie of Saxe-Altenburg (Alexandrina Mary Wilhelmina Catherine Charlotte Theresa Henrietta Louise Pauline Elizabeth Frederica Georgina; German: Alexandrine Marie Wilhelmine Katharine Charlotte Theresia Henriette Luise Pauline Elisabeth Friederike Georgine; 14 April 1818 – 9 January 1907) was Queen of Hanover from 18 November 1851 until 20 September 1866 as the wife of King George V. George V was a grandson of George III of the United Kingdom and his wife, Charlotte of Mecklenburg-Strelitz.

[1] In 1826, the family moved to Altenburg as a result of a transfer of territories among the various branches of the Ernestine Wettins, and Marie took the title Princess of Saxe-Altenburg in place of the previous.

Nevertheless, George never abdicated; he emigrated to Vienna, Austria, while Marie and her daughters remained at Herrenhausen Palace, then moving to Marienburg Castle, which was still under construction, in September 1867.

Marie succeeded in having the Hanoverian crown jewels and other precious items smuggled abroad, before finally leaving for Austria herself.

George V. died in 1878 on a travel in Paris where he had attempted to re-establish his Guelphic Legion, a military unit aimed at a re-conquest of his kingdom.