Count of Merenberg (German: Graf von Merenberg) is the title bestowed in 1868 by the reigning Prince of Waldeck and Pyrmont, George Victor, upon the morganatic wife and male-line descendants of Prince Nikolaus Wilhelm of Nassau (1832-1905), who married Natalia Alexandrovna Pushkina (1836-1913), former wife of Russian General Mikhail Leontievich von Dubelt.
Nikolaus was a son of William, Duke of Nassau and his second wife, Princess Pauline of Württemberg. He was also a younger half-brother of Adolphe, who was deposed by Prussia as last reigning Duke of Nassau in 1866, but succeeded as Grand Duke of Luxembourg in 1890. Natalia was a daughter of Alexander Pushkin, the most renowned Russian writer who ranked, however, only as a dvoryanin; an untitled member of the lower nobility. Therefore, Natalia was created Countess von Merenberg, a title without territory, as she was not legally permitted to share her husband's princely title or rank, even though his family had ceased to be hereditary rulers when the kingdom of Prussia annexed Nassau.
Through Pushkin, Natalia descends from Peter the Great's African protégé, Abram Petrovich Gannibal. Through her mother, Natalia descends from the Cossack leader Prince Petro Doroshenko.