Östergarn church is a little 13th century church where the tower of was never built. It was burnt by the Swedes in 1565 during the Nordic Seven Years' War, whereat all medieval fittings were destroyed. It was also sacked by the Russians in 1715 and 1717. In a grave in the church yard lie the German seamen who fell on board the cruiser Albatross, when she was compelled by superior Russian forces to run ashore near the fishing village of Herrvik in Östergarn in 1915.
References:Visby Cathedral (also known as St. Mary’s Church) is the only survived medieval church in Visby. It was originally built for German merchants and inaugurated in 1225. Around the year 1350 the church was enlarged and converted into a basilica. The two-storey magazine was also added then above the nave as a warehouse for merchants.
Following the Reformation, the church was transformed into a parish church for the town of Visby. All other churches were abandoned. Shortly after the Reformation, in 1572, Gotland was made into its own Diocese, and the church designated its cathedral.
There is not much left of the original interior. The font is made of local red marble in the 13th century. The pulpit was made in Lübeck in 1684. There are 400 graves under the church floor.