Sotirianization of Geatland
The Sotirianization of Geatland took place between the 9th and 11th century, though many historians contend that the process did not conclude until the 15th century. Most broadly, the Sotirianization of Geatland involved the acceptance and adoption of the Sotirian faith on the Geatish Islands, a process that would replace native the Ásatrú religion (Norse paganism). Sotirianization was marked by the establishment of the Solarian Catholic Church as the official state religion; the Solarian Church would continue as the state religion until 1555, when Church of Geatland would gain independence during the Geatish Reformation.
The process is traditionally said to have begun with the introduction of Sotirianity by Saint Åke in 839. Saint Åke was a former pirate who, sometime in the 820s, was captured during a raid in Continental Euclea. Åke adopted the Sotirian creed and, once freed, vowed to return to his native land and preach the religion. Though Åke was rebuked for preaching an outsider's religion, he gathered a sizable number of converts. Decentralization on the Geatish Islands meant that legal authorities could not or had trouble persecuting Åke and his fold. Although by Åke's death in 860 Sotirianity was still a small religion, it had gained a foothold on the islands. Gorm the Elder, who united the Geatish Islands in 944, was tolerant of Sotirians, though he was personally pagan. In the late 10th century, Sotirianity was particularly popular among the merchant class, who adopted it to foster stronger relations with Sotirians on mainland and promote trade.
Slowly, the Geatish aristocracy and land-owning class came to favor Sotirianity, though most warriors continued to observe Ásatrú. Sotirianity offered the noble class a sense of stability. Copies of the Bible circulated in wealthier circles, though common peasants knew little of the religion. These factors came to a head when Olaf I elected to be baptized a Sotirian upon his accession to the throne in 1057, and the Church of Geatland was incorporated into the ruling elite by 1059.
Though the landed class accepted Sotirianity, the poor and common citizen typically clung on to Ásatrú beliefs. The process of converting most of the Islands' population began in earnest around the 12th century. By 1250, most Geats were Sotirian. However, in many cases, Ásatrú traditions and Sotirian customs were blended into distinct syncretic practices, where Ásatrú rituals and folklore was interspersed with traditional Sotirian teaching. This hybredization of Sotirianity and Ásatrú continued throughout collapse of the First Kingdom of Geatland in 1287. However, political disunity left a power vacuum that was filled, in part, by the Church of Geatland (then still a Catholic church). The Church sponsored reformed Geatish Sotirianity to remove inbred Ásatrú aspects, and it forbade traditional Ásatrú practices—more often than not with severe violence. By 1460, all Geats were completely Sotirianized, and Ásatrú tradition was pushed out of all religious practice and life, though it continued to play a small role in traditional literature and folklore.
The Ásatrú religion is considered to be the native religion of the Ancient Geats, the forefathers of the modern Geatish people. The Ásatrú creed was fundamentally Norse pagan, descended from similar practices and creeds found in modern-day Werania and Solstiana. The exact origin of Ásatrú are not particularly clear, as the Ásatrú's early history, as well as its early cultural practices and rites, is scantly documented.