Johann Georg Robertus was born on 13 December 1752 in Schriesheim. He immigrated to Denmark (Schleswig-Holstein) where on 12 November 1760 he married Apollonia Barthold in Thorning. In 1764, the family immigrated to Russia, arriving in Balzer on 28 August 1765. They and their two daughters are recorded there on the 1767 census in Household No. 9.
- Eichhorn, Alexander, Jacob & Mary Eichhorn. The Immigration of German Colonists to Denmark and Their Subsequent Emigration to Russia in the Years 1759-1766 (Deiningen, Germany: Drukerei und Verlag Steinmeier GmbH & Co. Kg, 2012): B-1390.
- Lang, Gerhard. German Colonists of Denmark on the Volga.
- Mai, Brent Alan. 1798 Census of the German Colonies along the Volga (Lincoln, NE: American Historical Society of Germans from Russia, 1999): Bz037, Bz047.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 1 (Göttingen: Göttinger Arbeitskreis, 1999): 74.