Elizaveta Mavrikievna (born Princess Elisabeth Auguste Marie Agnes of Saxe-Altenburg; 25 January 1865 in Meiningen, Germany – 24 March 1927, Leipzig, Germany), was a Russian Grand Duchess by marriage. She was the wife of Grand Duke Konstantin Konstantinovich of Russia (1858–1915), whom she married in 1884 in Saint Petersburg, Russia.

Princess Elisabeth, as she was usually known, was the second child of Prince Moritz of Saxe-Altenburg (1829–1907) and his wife, Princess Augusta of Saxe-Meiningen (1843–1919). During her youth she made several trips around Europe visiting her relatives.

In 1882, when she was sixteen, she met her second cousin, Grand Duke Constantine Constantinovich of Russia in Altenburg. His mother and her father were first cousins; in addition to that, they shared Emperor Pavel I as a common ancestor. There was immediately some talk of marriage. However, although she said she was ready to marry Constantine, he hesitated, although he was by then 24 years old. When she left, he promised to often write, but he never did, as he was tremendously shy. Nevertheless, he did write several poems about her. In 1884, she visited Russia and the wedding was announced, although she manifested her wish to keep her Lutheran faith, which was a serious blow for her future husband, since he believed firmly in the Russian Orthodox Church. Even worse was the fact that she refused to kiss the cross held in Orthodox services.

On the wedding day, which took place on 27 April 1884, she wrote to him a reassuring letter, saying that “I promise you that I will never do anything to anger nor hurt you through our divided religions… I can only tell you again, how very much I love you.

The marriage was a success, although Grand Duke Konstantin secretly kept male lovers. Constantine and Elizaveta had nine children:

Prince Ioann (1886–1918)
Prince Gavriil (1887–1955)
Princess Tatiana (1890–1979)
Prince Konstantine (1891–1918)
Prince Oleg (1892–1914)
Prince Igor (1894–1918)
Prince Georgi (1903–1938)
Princess Natalia (died at exactly two months, 1905)
Princess Vera (1906–2001)

Grand Duchess Elizaveta Mavrikievna, or “Mavra” as she was known within the Romanov family, was a popular figure, and got on quite well with her nephew, Tsar Nicholas II.