The Blank family is a family of Jews, some of whom converted to Orthodox Christianity in the Russian Empire, mostly notable as the immediate ancestry of the maternal grandfather of Vladimir Lenin according to various published researchers who suggest that Lenin's maternal grandfather was a Jewish convert to Christianity (Alexander Blank). Whether or not Lenin, whose matrilineal "Blank" surname also traces to non-Jewish German roots, was actually partly descended from the Jewish Blank family remains contested.
Moshe Itzkovich Blank (Russian: Мойша Ицкович Бланк) baptized as Dmitry Blank (c. 1758-after 1844) was a Jewish vodka-franchised tavern keeper from Shtetl Starokonstantynów, Volhynian Voivodeship (now Ukraine). His tavern in Starokonastantinovo brought him around 10 silver roubles. He also rented a plot of land in Novohrad-Volynskyi uyezd, Volhynian Governorate where he grew chicory. He sent his sons into a secular Russian school instead of a traditional religious Jewish cheder which was unusual in those times.
Most of his life story is known through the documents related to his complicated feud with the local kahal. In 1803, the kahal accused Moshe of stealing hay; in 1805, they accused him of selling cheaper ordinary vodka as a more expensive "fruit vodka" brand. The official courts cleared Moshe on both counts. In 1806, Moshe, in turn, accused the kahal of shielding local Jews from taxes and their children from conscription into the Russian Army. In 1808, 22 local Jews accused Moshe Blank of arson that destroyed or damaged many houses in Starokonastantinovo, including the Blanks' own house. Some researchers believe that the arson charges were true and that Blank indeed was a pyromaniac, while others consider the charges as a false report done as a revenge for his reports. In 1809, Novohrad-Volynian magistrate cleared Blank from the arson charges, but the family had to move to Zhitomir.