History of the orthodox church in Finland
The Christian faith spread to eastern Finland from Novgorod in the 12th century through the activities of monks and traders, but the real religious centres for the region were the monasteries, two of which were founded on islands in Lake Ladoga, those of Valamo (Russ. Valaam) early in the second millennium and Konevitsa (Russ. Konevets) towards the end of the 14th century. Later, in the 16th century, a monastery was founded at Petsamo (Russ. Pechenga) beside the Arctic Ocean. All of these monasteries were destroyed in the wars of the 16th and 17th century, in the course of which some of the western parts of Karelia were incorporated into the Kingdom of Sweden and part of their population fled to Central Russia while some remained in their home areas and adopted the Lutheran religion. When the parts of Karelia around Lake Ladoga were re-captured by Peter the Great in the early 18th century, the Orthodox faith also regained its status in the area, and the monasteries of Valamo and Konevitsa were rebuilt on their historic sites. The northern monastery of Petsamo was re-established at the end of the 19th century, and around the same time a community of nuns was set up at Kivennapa on the Karelian Isthmus which later became the Convent of Lintula.After the war between Sweden and Russia came to an end with the Treaty of Hamina in 1809, the province of Viipuri (Russ. Vyborg) was annexed to Finland, which had become a Grand Duchy of the Russian Empire, and the Orthodox population of Finland increased by a factor of ten. The outcome of these political changes was that Orthodox merchants, soldiers and officials gradually moved to live permanently in other towns throughout the country. At the same time a separate church administration for Finland was set up under the Diocese of St. Petersburg, and in 1892 this became an independent Diocese of Finland and Viipuri, serving a varied population made up of Karelians, Russians, Finns and Skolt Saame.
When Finland gained its independence as a consequence of the Russian Revolution, the Orthodox Church acquired the status of a national church alongside the Lutheran Church. In 1921 Patriarch Tikhon of Russia granted autonomy to the Finnish church, and in view of the political turmoil in the Soviet Union and the difficulties of maintaining contacts in that direction, the Orthodox Synod of Finland applied to be taken under the protection of the Patriarchate of Constantinople. This was granted in a document (Gk. tomos) of 6.7.1923, under which the Finnish Orthodox Church became an autonomous archbishopric of the Patriarchate of Constantinople.
In the years preceding the Second World War the focus of activities was on Karelia, where the majority of the parishes were, but after the war, with the resettlement of the population of the ceded territories of Karelia over the rest of Finland, a new, comprehensive network of parishes was created, new churches were built, mainly in the 1950s, and the country was divided at first into two dioceses, that of Karelia, covering the central and eastern parts of the country, and that of Helsinki, covering the southern part, western part and Lapland in the north. It was in 1979 that the position of Bishop of Joensuu was created to provide a suffragan bishop to assist the archbishop, and later in the same year the Diocese of Oulu was created and a metropolitan chosen for it. This new diocese began to function in January 1980.