Maria Alexandrovna (Marie of Hesse and by Rhine)
Marie of Hesse and by Rhine was, under the name Maria Alexandrovna , Empress of Russia as the first wife of Emperor Alexander II, having been born a German princess. The Mariinsky Theatre and the city of Mariehamn in land are named after her.
Marie was the youngest of seven children born in Darmstadt to the marriage of Ludwig II, Grand Duke of Hesse and his first cousin, Princess Wilhelmine of Baden , a sister of the Russian Empress consort, Elizaveta Alexeievna. The four youngest of Grand Duchess Wilhelmines children are purported to have been the biological children of Baron August von Senarclens de Grancy, although even after their mothers death Grand Duke Ludwig acknowledged as his own children the two who lived to adulthood Alexander and Marie, whose marriage to the future Russian emperor he approved.
Source: Wikipedia