Ancient DNA reveals gradual shift after Rome’s fall

In southern Germany, researchers analysed ancient DNA from 258 individuals buried between 400 and 700 AD, revealing that the collapse of the Western Roman Empire did not cause a sudden takeover by invading groups.

Instead, the genetic evidence indicates a slow integration of people through intermarriage between local populations and newcomers.

Before 470 AD, people with northern European ancestry lived alongside those with Roman connections, but after that year, people with Roman ancestry began moving into rural areas and mixing with the existing communities. The study focused on row-grave cemeteries, which appeared after 450 AD and contained people buried with personal items. Scientists combined DNA analysis with archaeological data, including radiocarbon dating and bone analysis, to understand who lived where and how families were connected.

They found that people with different backgrounds were not buried in distinct ways, suggesting a merging of cultures rather than a clash. Researchers reconstructed family trees and discovered that close-kin marriage was rare, monogamy was common, and many children had living grandparents. Life expectancy was approximately 43 years for men and 40 years for women, and nearly a quarter of children experienced the loss of a parent before age ten.

Over 150 years, the genetic makeup of the region evolved into something resembling modern central European populations, demonstrating a gradual transformation rather than a swift replacement of one people by another.