Thomas Ortmann, a farmer, his wife Maria Wallborg, and their children (Johann Michael, age 19; Anna Maria, age 17; Maria Walpurga, age 13; Maria Eva, age 10; Maria Magdalena, age 8) settled in the Volga German colony of Herzog on 14 July 1766 and are recorded there on the 1767 census in Household No. 3.
In 1786, Thomas & Michael Ortmann and their families moved from Herzog to Semenovka.
Michael Ortmann and his family are recorded on the 1798 census of Semenovka in Household No. Se57.
Nikolaus Ortmann, son of Michael Ortmann, and his family are recorded on the 1834 census of Mariental in Household No. 37.
The 1767 census records that Thomas Ortmann came from the German village of Kelheim in Bayern (Bavaria).
- 1834 Mariental Census (Household No. 37).
- 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): Se57, Mv0817.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 2 (Göttingen: Der Göttinger Arbeitskreis, 2001): 88.