Catherine I of Russia Catherine I of Russia Catherine I (, born , later known as Marta Samuilovna Skavronskaya; – ) was the second wife of Peter the Great and Empress of Russia from 1725 until her death. The life of Catherine I was said by Voltaire to be nearly as extraordinary as that of Peter the Great himself. There are no documents that confirm her origins. Said to have been born on 15 April 1684 (o.s. 5 April), she was originally named Marta Helena Skowrońska. Marta was the daughter of Samuel Skowroński (later spelt "Samuil Skavronsky"), a Roman Catholic peasant from the Polish–Lithuanian
Duke Peter Alexandrovich of Oldenburg Duke Peter Alexandrovich of Oldenburg Peter Alexandrovich of Oldenburg (Duke Peter Friedrich Georg von Oldenburg) (21 November 1868 – 11 March 1924) was the first husband of Grand Duchess Olga Alexandrovna of Russia, the youngest sister of Tsar Nicholas II. He was born in Saint Petersburg, the only child of Duke Alexander Petrovich of Oldenburg (1844–1932) and Eugénie Maximilianovna of Leuchtenberg (1845–1925). His mother was a granddaughter of Tsar Nicholas I of Russia through Nicholas's daughter, Grand Duchess Maria Nikolayevna, and his father was a great-grandson of Tsar Paul I of Russia through his paternal grandmother Grand Duchess Catherine Pavlovna.