Johann Müller and his wife Johanna Charlotta settled in the Volga German colony of Schäfer on 1 August 1766.
Johann died and his widow remarried to Ignatz Bergstein. They are recorded there on the 1767 census in Household No. 41.
The 1767 census records that the widow Johanna Charlotta Müller came from the German village of Keller in the region of Brandenburg.
- Pleve, Igor. Einwanderung in das Wolgagebiet, 1764-1767 Band 4 (Göttingen: Göttinger Arbeitskreis, 2008): 100.