The latest genetic study has brought new insights into our ancestors in southern Germany, Bavaria and Baden-Württemberg. The Celts lived here in the Iron Age. The Celts formed the Hallstadt culture (800 to 450 BC) and the Latten culture (450 to 50 BC).
In the first century AD, immigrants came from the north. The Germanic tribes did not drive out the Celts but merged. Nevertheless, there were more immigrants than natives, and Roman historians already referred to southern Germany as Germania.
The third migration then followed in the early Middle Ages. Slavs settled in the northeast and southern Germany. The settlement of northeast Germany is fully known to us. The settlement of southern Germany, however, is completely new and unknown. The genetic study has shown that 12 percent of southern Germans are descended from the Slavs.
This latest research is also interesting for Austria and Slovenia. The medieval agricultural colonization of these two countries took place precisely with farmers from southern Germany.
Source
Felicitas Schmitt, Angela Mötsch, Joscha Gretzinger, Johannes Krause, Stephen Schieffels in drugi, Evidence for dynastic succession among early Celtic elites in Central Europe, Nature, 3. 6. 2024.