Those who are included in the Center's definition of "Volga German" originated from a variety of places in Europe. Determining that place of origin can be a very difficult task. The Holy Roman Empire was actually made up of hundreds of small kingdoms, principalities, duchies, counties, Free Imperial Cities, and a host of other geographic entities, many not contiguous to other parts of the same entity.
Some of those who came to be known as the Volga Germans actually came from France, Sweden, Hungary, Poland, Switzerland, Austria, Italy, or England. Yet another group were actually ethnic Germans, but they had settled earlier in Denmark before immigrating to Russia.
The surnames of those families for which origins have been confirmed by the Center for Volga German Studies can be located through the Surnames link.
Decker, K. P., Cott, Joachim, Cott, Susanne, & Geschichtswerkstatt Büdingen, publisher. (2015). Die Auswanderung von 1766/67 aus der Grafschaft Ysenburg-Büdingen nach Russland : Soziale und wirtschaftliche Hintergründe anhand ausgewählter Dokumente Mit einer Namensliste der Emigranten aus der Grafschaft Ysenburg-Büdingen. Büdingen, Hess: Geschichtswerkstatt Büdingen.