I-L38
Present day distribution is generally limited to the Upper Rhine and British Isles. Starting from the Upper Rhine, I-L38 spread during the Early Bronze Age in an area between Rhine, Danube and Elbe and I-L38 migrated in the Late Iron Age with the Celtic La Tène people, through Belgium, to the British Isles.
Haplogroup I-L38 was found in the skeletal remains of Lichtenstein Cave, a Bronze Age archaeological site in central Germany associated with artifacts of the Urnfield culture. Of the 19 males represented in the cave, 15 yielded the full 12 tested STR values, with twelve showing I-L38, one R1b, and two R1a. Of the 21 females in the cave, the majority were mtDNA H, with mtDNA U5b the runner-up. No radio-carbon dating was discussed and no metrics were assigned based on the adult remains, which are thought to be about 3000 years old. The small sample and their possible familial connections do not permit drawing conclusions regarding the overall contemporary population mixture.
The distribution and diversity of continental I-L38 samples with known geographical origin suggests that the Upper Rhine area (Rhineland–Palatinate) is the most likely point of origin of I-L38.
Almost half of all present I-L38 (aka I2a2b) samples (49%) has a MCRA that goes back to time frames corresponding with Late Bronze Age (in casu Urnfield culture: 26%) and Iron Age cultures (23%). The core of the La Tène culture matches with the continental heartland of I-L38. From this area the La Tène culture spread to the British Isles.
All network analyses of the I-L38 group contain a star-structure, indicating a demographic explosion and/or migration. Looking at the Rhineland demographics this could indicate a major migration in the times of the Great Migrations. It is a known fact that Ripuarian Francs migrated from the Rhine area to the west.
German, French and Flemish I-L38 forefathers came to the British Isles with the Norman invasion of the 11th century. This also explains the presence of I-L38 in the Norman kingdom Sicily.
In the 12th century I-L38 travelled to Eastern Europe in a migration called the Ostsiedlung. The bulk of these colonists, travelling to Hungary, came from Luxembourg, the Moselle region, the Rhineland, and the southern Low Countries.
In the 17th century the Thirty Years' War shuffled the I-L38 heartland, leading to migrations to Britain, Ireland and North America. This war also made fleeing farmers nomadic (known as the white gypsies or Yenishe/Jenische).
Most Dutch samples have a demonstrable and relatively recent German or Flemish background.
Read more about this topic: Haplogroup I2 (Y-DNA), Subclades