Short answers, pulled from the story.
Haplogroup I-M253 is defined by single nucleotide polymorphisms including M253, M307.2/P203.2, and M450/S109. A 2017 ISOGG report lists over thirty distinct mutations that characterize this lineage.
Haplogroup I1 first appeared among Upper Paleolithic European hunter-gatherers as a minor lineage before the Nordic Bronze Age. The time to most recent common ancestor calculation places the origin near 2600 BC according to Y-Full results published in January 2022.
Alexander Hamilton, Andrew Jackson, Ludwig van Beethoven, Leo Tolstoy, Robert E. Lee, William Bradford, Birger Jarl, Sting, Chris Pine, and PewDiePie all carry Haplogroup I-M253. Birger Jarl was exhumed and tested in 2002 confirming his status as an I-M253 carrier.
Haplogroup I-M253 reaches peak frequencies in Sweden where 52 percent of males in Västra Götaland County carry it. Western Finland shows over 50 percent prevalence in Satakunta province while Norway records 37% and Denmark sits at 34.8%.
Germanic tribes began moving out of southern Scandinavia and northern Germany around 900 BC into lands between the Elbe and Oder rivers. A second wave crossed the Baltic Sea between 600 and 300 BC to settle alongside the Vistula river forming the Wielbark culture associated with the Goths.