Heinrich Mertes, son of Anton Mertes, married Sophia Baur, a daughter of Dionysii Baur, on 4 February 1750 in the Catholic Church in Bombogen, 9 kilometers east of Wittlich. They had six known children, the four oldest were baptized in Bombogen, and the two youngest in Wittlich: (1) Andreas, on 9 December 1750; (2) Susanna, on 8 September 1753; (3) Anna Catharina, on 9 April 1755; (4) Anna Catharina (again), on 22 November 1757; (5) Maria Agatha, on 21 March 1760; and (6) Johann Peter, on 23 January 1762.
Heinrich Mertes and his family emigrated to Russia arriving in the colony of Mariental on 14 June 1766. They are recorded there in the 1767 Census in Household No. 41.
On the 1798 Mariental Census, daughter Anna Catharina is recorded in Household No. Mt68, along with her mother Sophia Baur. Other descendants are recorded in Households No. Mt33, Mt37, & Mt59.
- Mai, Brent Alan. 1798 Census of the German Colonies along the Volga: Economy, Population, and Agriculture (Lincoln, NE: American Historical Society of Germans from Russia, 1999): Mt33, Mt59.
- Parish records of Bombogen (LDS Film No. 585833).
- Parish records of Wittlich (LDS Film No. 531291).
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 3 (Göttingen: Nordost-Institut, 2005): 105.