To understand Odinism—and the way that it became a religion entangled with racism, exclusion, and American prison culture—you need to start with the original Scandinavian pagans. These groups worshipped Norse gods through songs and ceremonies, celebrating the mythology of gods like Thor and Odin, who went by many names. Between the 8th and 12th centuries AD, Christians "explained" to the heathens about the One True God, and so-long went paganism, until the mid-1800s, when a nationalistic climate led Scandinavian countries to rediscover their own history. They found something to call their own—Norse Gods—and rebirthed the religion into Germanic neopaganism.
In 1936, Australian author Alexander Rud Mills established the First Anglecyn Church of Odin, which claimed Odinism as "the indigenous religion of the northern European people." In his opening liturgical text, he mentioned "the fall from grace of the White Race by being untrue to the spirit of their forefathers." Else Christensen, a Danish woman, was struck by the work. After WWII, Christensen and her husband Alex emigrated to Canada and founded the Odinist Study Group after WWII with the claim that "religion is in our genes." After Alex's death in 1971, she moved to the United States and published The Odinist newsletter.