Male line information: Y-group I1

All members of Y-group I1 can trace their Y-chromosomes back to a single man who is thought to have lived about 15 to 20 thousand years ago, probably in Europe. This man belonged to a group of hunter-gatherers that may have sought refuge during the last Ice Age in the region now known as the Balkans. Later the descendants of this group spread northward, taking part in the recolonization of Northern Europe following the retreat of the glaciers.

Today, members of Y-group I1 are found at the highest frequency in Europe, where about 20 percent of all males belong to this Y-group. Members of Y-group I1 are also found in Northern parts of Asia, but at a considerably lower frequency. Within Europe, the highest frequency of Y-group I1 members is in Scandinavia, where it reaches about 35 percent. As a result, Y-group I1 is sometimes used as a marker for the genetic impact of Vikings on other populations. The presence of Y-group I1 members among the Inuit of Greenland and Maori of New Zealand is the result of more recent contact between these populations and Europeans.

Note that Y-group I1 was previously called I1a. The name was changed to accord with the latest developments in the scientific literature.