" Island populations often breed strange and interesting genomes. Because Iceland is so small, with a precisely known chronology of inhabitation to the present day, we have the most comprehensive log of everyone who has ever lived there since the ninth century. There have only been thirty-five generations of Icelanders. Since the end of the era of settlement, there’s been very little immigration into Iceland of note. "

― Adam Rutherford , A Brief History of Everyone Who Ever Lived: The Stories in Our Genes