STOCKHOLM, SWEDEN—Analysis of human remains from the Viking town of Sigtuna dating to the tenth to twelfth century finds that at least half the population consisted of immigrants, according to a report in The Local. Researchers from Stockholm University studied DNA and strontium isotopes from the remains of 38 people to determine where they originated. They found that around half came from the nearby Lake Mälaren area, but the other half came from areas as far off as Ukraine and the British Isles. The evidence suggests that Sigtuna was the Viking Age equivalent of London or Shanghai today, says Anders Götherström of Stockholm University, a place that attracted ambitious people interested in working their way up in the world. Sigtuna was one of Sweden’s first cities, founded in 980, and soon reached a population of 10,000, roughly the same as London at the time. Maja Krzewinska of Stockholm University points out that the Vikings are generally thought of as travelers and adventurers, but the new findings suggest they also played host to those who came from afar. To read in-depth about an island in Sweden that grew extremely wealthy during the Viking Age, go to “Hoards of the Vikings.“