Princess Marie of Nassau (German: Prinzessin Marie Wilhelmine Friederike Elisabeth von Nassau; 29 January 1825 – 24 March 1902) was the eighth child and fourth daughter of William, Duke of Nassau and wife of Hermann, 4th Prince of Wied. She was the mother of Queen Elisabeth of Romania.

Marie was born at Biebrich, Duchy of Nassau the eighth child and fourth daughter of William, Duke of Nassau (1792–1839) by his first wife, Princess Louise of Saxe-Hildburghausen (1794–1825), daughter of Frederick, Duke of Saxe-Altenburg.

She was sister of:

And half sister of:

Marie married on 20 June 1842 in Biebrich, Hermann, Prince of Wied (1814–1864), elder son of Johann August Carl, Prince of Wied and Princess Sophie Auguste of Solms-Braunfels. They had three children:

According to the German writer and socialite Marie von Bunsen (1860–1941), Princess Marie is reported to have had a relationship with the Baden politician Franz von Roggenbach (1825–1907) to whom she even might have been married morganatically after her husband's death.

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