The widow of Johann Georg Sierwald is recorded on the 1767 census of Stahl am Karaman in Household No. 46 as the wife of Johannes Martin. They had settled in Stahl am Karaman on 22 June 1767.
The 1767 census does not record from where Johann Georg Sierwald came.
There are no known surviving male lines of this family among the Volga German colonies.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 4 (Göttingen: Göttinger Arbeitskreis, 2008): 203.