Religion
The settlement of the Aland Islands by the Vikings from the territory of modern Sweden began at around the year 500. By 800, the first Viking camps appeared in continental Finland. By the 12th century, royal power was consolidated in Sweden, which contributed to the strengthening of its influence on Finland. At the same time, due to the rivalry between the papacy and the Holy Roman Empire, at the behest of the pope, new archbishoprics were founded – in Lund (1104) and Uppsala (1164). This was done in order to use a political vacuum to take a stronger position against the policies of Novgorod. And also in order to eliminate the Archbishop of Bremen, distinguished by excessive loyalty to the emperor. All this contributed to missionary activity in a more organized form than before. In the medieval sources three Crusades to Finland are mentioned, which historians date 1157, 1249-1250 and 1293-1300.
Crusades
The first Swedish crusade was led, in accordance with church tradition, by a British monk, Heinrich. Under the protection of King Eric IX, he embarked on a missionary expedition to southwestern Finland, which became known to descendants due to the subsequent canonization of Henry and declaring him patron Abo (Turku), since, according to legend, the monk did good and miracles in his lifetime.
His killing by local residents was the exception rather than the rule, since in general the Christianization took place in a calm atmosphere.
Around 1220, the Swedes founded the episcopal department in Finland. The first bishop was the British priest Thomas. During his time, the Swedes, probably in alliance with the Sword, armed the army under the leadership of Jarl Birger (according to other sources, Ulf Fassi) to weaken the influence of Novgorod, but failed in the battle with the army of Prince Alexander Nevsky on the tributary of the Neva River Izhora in 1240. Subsequently, a memorial stone was installed at the scene of the battle, and the prince who took a personal part in it received an addition to the name “Nevsky”.
Jarl Birger conquered the Tavastland in 1249 and founded the Tavastehus castle.
The decisive battles for the capture of the eastern coast of the Gulf of Finland and the internal parts of the country took place at the end of the XIII and the beginning of the XIV century. Marshal Torkel Knutsson, during the third crusade in 1293, marched on the Novgorodians, conquered south-western Karelia and founded the Vyborg castle there, and in 1300 the Swedes erected the fortress of Landskrona on the banks of the Neva River, which a year later was taken by the Novgorodians led by the son of Alexander Nevsky, Prince Andrei Gorodetsky, after which the fortress was destroyed.
Military operations between the Swedes and Novgorod continued almost continuously until 1323, when the Swedish king Magnus Eriksson, with the assistance of Hansa, concluded the Novgorod Orekhovsky treaty (on Orekhovy island at the mouth of the Neva River) with the Novgorod prince Yuri Daniilovich . This contract established the eastern boundary of the Swedish possessions.
It was not only a political border, but also a border that further divided two religions and two cultures. Finland and its inhabitants were mainly associated with the Swedish state and the Catholic Church. The settlements of Rauma, Porvoo, Pori and Naantali were the first to receive city rights along with Turku and Vyborg.
Sources:
Essays on the history of Finland from ancient times to the beginning of the 20th century
Brief history of Finland
The history of the Finnish people
Historiallinen Arkisto (“Historical Archive”) // Periodicals of the Finnish Historical Society.