Here is the regional frequency map from the study. Noteworthy: The northwestern region with more than 98% R1b frequencies is also high in Rh- blood. Strange: Northern Ireland shows with less than 15% while recent studies show more than 27%. The region that is now Northern Ireland was long inhabited by native Gaels. It was made up of several Gaelic kingdoms and territories and was part of the province of Ulster. In 1169, Ireland was invaded by a coalition of forces under the command of the English crown that quickly overran and occupied most of the island, beginning 800 years of foreign central authority. See also: Back to this: