Johann Georg Mattis (age 10) is recorded on the 1767 census of Kaneau in Household No. 57 along with his stepfather Georg Friedrich Baschka.
The Baschka family moved to the colony of Schaffhausen in 1786, and Johann Georg Mattis could have accompanied them there.
The 1767 census does not record a location from which Johann Georg Mattis 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 2 (Göttingen: Göttinger Arbeitskreis, 2001): 256.