Johann Georg Rupertus, son of Hans Georg & Anna Rupertus, was born on 13 December 1742 in Schriesheim. His father died 14 January 1752 and his mother remarried on 8 May 1753 to Leonhard Eisenhauer. She died in Schriesheim on 10 November 1767.
Johann Georg's older brother Johann Stephan (born 27 January 1740 in Schriesheim) and his family immigrated to Denmark (Schleswig-Holstein), arriving in Fredericia on 2 November 1759. Johann Georg followed, arriving in Fredericia on 1 May 1760. On 12 November 1760, Johann Georg married Apollonia Barthold in Thorning. They settled in the colony of Fridericia. They are last recorded among the Danish colonies on 26 April 1763. [Johann Stephan Rupertus returned to Schriesheim where his death is recorded on 22 January 1814.]
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.
The Eichhorns record that Georg Rupertus came from the German village of Schriesheim (Oberamt Heidelberg). The 1767 census records that he came from the German region of Kurpfalz.
- 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.
- Schuhmann, Karl. Familienbuch Schriesheim: 1650-1900 (Schriesheim, Germany: Odenwaldklub Schriesheim, 2004): #8172, #8176.