In 1792, widow Katharina Sophia Jergenson left Holstein.
Karl Jergenson is recorded on the 1798 census of Holstein along with a note that he is studying to be a joiner in Astrakhan.
Karl Jergenson and his family are recorded on the 1834 census of Holstein in Household No. 50 along with a note that they had relocated to the colony of Kraft.
Karl Jergenson and his family are recorded on the 1834 census of Kraft in Household No. 54.
- 1834 Holstein Census (Household No. 50).
- 1834 Kraft Census (Household No. 54).
- 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): Ho50.