Johann Gabriel Lederer, son of Johann Adam Lederer & Anna Katharina, was born and baptized on 12 April 1739 in Langenbeutingen, northeast of Heilbronn. [In 1976, the villages of Brettach and Langenbeutingen merged to become Langenbrettach.] He married Rosina Barbara Rau, daughter of Georg Konrad & Maria Eva Rau, on 23 February 1762 in the Heinsheim Lutheran Church.
They had no children when they decided to immigrate to Denmark (Schleswig-Holstein). Johann Gabriel, Rosina Barbara, and their servant Johann Adam Voigt departed from Altona, Duchy of Holstein, on 26 April 1762 under the leadership of Jakob Baumann. They arrived in the city of Flensburg, Duchy of Schleswig, on 1 May 1762.
In 1764 they had a daughter named Eva Christina. They lived in Denmark until 16 May 1765, when they immigrated to Russia.
Johann Gabriel's family arrived in the Volga German colony of Reinwald on 14 July 1766. They are recorded there on 1767 census in Household No. 30.
In 1798 they are registered on the Reinwald census in Household No. Rw26.
- Eichhorn, Alexander; Eichhorn Jacob & Mary. The Immigration of German Colonists to Denmark and Their Subsequent Emigration to Russia in the Years 1759-1766 (Deiningen: Steinmeier, 2012): 288, 500, & 680.
- 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): Rw26.
- Parish records of Heinsheim (LDS Film No. 1189292).
- Parish records of Langenbeutingen (LDS Film No. 1340222).
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 4 (Göttingen: Göttinger Arbeitskreis, 2008): 37.