Imagine a long stream of people walking day after day from Saltzburg to Berlin, creating a sensation as they trekked through innumerable northern German towns and cities wearing their unfamiliar Austrian style clothing. In 1982 a German postage stamp celebrated this event on the 250th anniversary of the arrival of Salzburg Emigrants in Prussia in 1732 (1732 Ankunft der Salzburger Emigranten in Preussen)…the image depicts grateful Protestants, who were expelled from their Catholic city of Salzburg in Austria, arriving at the border of Prussia. The emigrants were given sanctuary by Prussia’s Protestant King and were granted land and other benefits for populating vacant land in East Prussia.
Thirty one years later in 1763, some of the Austrians, along with many other Germans mostly from East Prussia, were enticed to emigrate across the nearby border into the Russian Empire. The German born Russian Empress Catherine the Great (born in 1729 as Sophie Friederike von Anhalt-Zerbst-Domburg in Stettin in Pommerania, Prussia) wanted industrious and skilled Germans to colonize her vast empire. Her proclamation offered generous incentives: exemption from military service, self-governance, tax breaks, freedom of religion, and 75 acres land for each family.
This is how it came to be that tight knit German communities were established all over Russia. For example in Kaunas, Lithuania (part of the Russian Empire at the time), the population was 5% German in the 1890 census. Other Germans located to Mitau and Riga, cities in the Latvian part of the Russian Empire that were already administered and populated by Germans who were descendants of citizens of the Monastic state of the Teutonic Order. Others became Volga Germans and some even moved to the Saint Petersburg area and became officials in the Russian government. For example, one of the Russian generals in WWI was Paul von Rennenkampf and another ethnic German, Maria Blank, the mother of Vladimir Lenin, was the granddaughter of Johann Groschopf.
I found a helpful map that shows some of the extent of German communities in eastern Europe. Although it does not show all of the Russian Empire, it does give an excellent graphic image of widespread German colonization. You can look at the map in my post: “Map of German Language Areas, produced after a 1910 census”.