Genealogy

Potemkin: ЛОТЕМКИН
This family is descended from Gans Alexandrovich, called Tarasii Potemkin after baptism. He departed from Poland to serve the Grand Prince Vasili Ivanovich who granted him hereditary estates. Many descendants of this Tarasii, the Potemkin family, served the Russian Throne in noble positions. For their service they were granted fiefdoms by the Emperors, and some were given distinguished positions and other tokens of the Monarchs’ favour.
....Potemkin Hereditary Commander (1800)
Details awaited.
Sources:
Ferrand, Jacques: Les Familles Princières de l'Ancien Empire de Russie Recueil Généalogique, 2ème édition [Paris 1998]
Mandrich, Donald R. & Placek, Joseph A.: Russian Heraldry and Nobility [Dramco Publishers, Boynton Beach, Florida 1992]
Marek, Miroslav: GENEALOGY.EU - http://genealogy.euweb.cz/
http://perso.chello.fr/users/s/sbelosselsky/arbregn.htm
Rietstap, J.B.: ARMORIAL GÉNÉRAL [2éme ed., G.B van Goor Zonen, Gouda 1884]
Shamà, Davide and Dominici Battelli, Andrea: GENEALOGIE DELLE DINASTIE ITALIANE - http://www.sardimpex.com
Taube, Professor Baron Michel Alexsandrovich, de: L'Empereur Paul I de Russie, Grand Maître de l'Ordre de Malte, et son Grand Prieuré Russe, [Paris 1955]
Theroff, Paul: An Online Gotha