Overview
I1j (CTS10082) represents a North Sea–Baltic transitional branch of I1 that crystallized during the Late Nordic Bronze Age, a period marked by intensified maritime connectivity between Denmark, southern Sweden, the Norwegian coast, and the North German lowlands. The lineage likely belonged to coastal communities specializing in trade, seafaring and proto-Germanic cultural exchanges. Unlike the major I1a (L22) and I1b (Z58) expansions, I1j expanded more gradually, reflecting stable but localized demographic continuity.
Geographic distribution
Today, I1j reaches highest frequencies in Denmark, southern Norway, Schleswig-Holstein, Lower Saxony and coastal Sweden. Moderate levels appear in the Netherlands and the British Isles, mainly through Viking and Anglo-Saxon migrations. Rare occurrences in Poland and Lithuania reflect Baltic maritime links during the Iron Age.
Ancient DNA
- Late Bronze Age burials from Jutland and the Danish islands show upstream I1-Z58 ancestry ancestral to CTS10082.
- Iron Age individuals from the North Sea coast and Frisia demonstrate phylogenetic proximity to early I1j.
- Some Viking Age remains from southern Norway and Denmark fall within the CTS10082 > Y1300 cluster.
Phylogeny & subclades
I1j is part of the Z58 > Z138 phylogenetic framework but branches independently of major continental radiations such as Z63 and Z2041. CTS10082, Y1300 and related markers define a distinctive North Sea coastal clade with several region-specific micro-branches.
- I1-Y1300
- I1-BY46685
- Basal CTS10082* branches
Notes & context
I1j is particularly informative for mapping Iron Age and early medieval maritime movements in northern Europe. Its distribution closely follows cultural and economic zones tied to early Germanic-speaking populations.
References & external links