Karl Wilhelm von Holstein, a Polish nobleman, and his wife Maria settled in the Volga German colony of Merkel on 28 August 1766. They are recorded there on the 1767 census in Household No. 44.
The 1767 census records that Karl Wilhelm von Holstein came from the German region of Mecklenburg.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 3 (Göttingen: Göttinger Arbeitskreis, 2005): 128.