By the year 1000 Christianity was well established on Öland, and small churches were erected all over the island. All churches were built of wood, except the one in Resmo. This was built in 1100 and its construction shows Danish influence. At this time, the Danes very much wanted to gain power on Öland and the church at Resmo may have been built to demonstrate this intention
From about 1100 and a hundred years on, all parish churches on Öland and the Möre coast were built of stone.
The Church and Crown had these churches erected in order to demonstrate their authority. Öland and Möre were important regions at this time. The King ´s own church was the church at Köping. One of these fortified churches still remain, Källa church in the north-east of Öland.
Chapels were built in the most important fishing-villages. Generally speaking, churches were built in all places were people met or traded. The most important chapels were the chapel of St. Birgitta in Sikavarp, the parish of Bredsättra and the chapel of St. Johannes in Kyrkhamn, the parish of Ås.
A number of convents, amongst them the ones in Vadstena and Kalmar, owned land on Öland.