 Olga was born at Pavlovsk Palace near Saint Petersburg on 3 September [O.S. 22 August] 1851. She was the second child and elder daughter of Grand Duke Constantine Nikolaievich and his wife, Grand Duchess Alexandra, a former princess of Saxe-Altenburg. Through her father, Olga was a granddaughter of Tsar Nicholas I, a niece of Tsar Alexander II and first cousin of Tsar Alexander III.
