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The series will start to air on Swedish television this Wednesday, and when channel SVT began promoting it last week, some people reacted on social media with disbelief and anger.
The documentary will look at DNA technology which has revealed more about how Sweden was populated after the Ice Age and detailing how the first pioneers in the country were dark-skinned with blue eyes and came from the south.
Another population of people who had paler skin and a variety of eye and hair colors arrived around the same time from the east. The two peoples are thought to have mixed fairly quickly, and Nordic people eventually became lighter skinned, allowing them to increase their vitamin D production to survive in the dark winters.
Some Twitter users took the information advertised in the documentary as some sort of conspiracy aimed at making people more open to immigration. "Indoctrination continues," one said.
Others were quick to challenge the skepticism.
One person joked it was simply impossible, as his ancestors were "frozen in the ice sheet" before it melted.
