Catherine I of Russia to bribe the Ottoman grand vizier Baltacı Mehmet Pasha into allowing a retreat. Mehmet allowed the retreat, whether motivated by the bribe or considerations of trade and diplomacy. In any case Peter credited Catherine and proceeded to marry her again (this time officially) at Saint Isaac's Cathedral in St. Petersburg on 9 February 1712. Catherine was Peter's second wife; he had previously married and divorced Eudoxia Lopukhina, who had borne him the Tsarevich Alexis Petrovich. Upon their wedding, Catherine took the style of her husband and became Tsarina. When Peter elevated the Russian Tsardom to Empire, Catherine became Empress. The
Anna of Russia husband, but her enemies said she conducted a love affair with Ernst Johann von Biron, a prominent courtier, for many years. In 1730, Tsar Peter II (grandson of Anna's uncle Peter the Great) died childless at a young age. His death rendered extinct the male line of the Romanov dynasty, which had ruled Russia for over a century, since 1613. There were five possible candidates for the throne: the three surviving daughters of Ivan V, namely Catherine (b.1691), Anna herself (b.1693) and Praskovya (b.1694), and the two surviving daughters of Peter the Great, namely Anna (b.1708) and Elizabeth (b.1709). Ivan