At the beginning of the Kalmar Union age Sandemar was owned by the Teutonic Order of Livonia. Erik Axelsson Tott bought all the Order's property in Sweden in 1467. During the 1500s the ownership was unknown. In the 1600s the Sandemar belonged to families Oxenstierna, Bonde and Falkenberg. The Royal Council and president Gabriel Falkenberg completed the present main building around the year 1693. Sandemar is today privately owned by Karin Mattson Nordin, daughter of the real estate developer John Mattson.
The main building of Sandemar is made of wood, covered with tiles and the water side plates to protect against sea winds. The farm escaped the Russian ravages in 1719, probably through the deterrent effect of the nearby Dalarö Fortress had, and have therefore preserved the Carolinian period decorations. The English garden is added later with greenhouse, vegetable and fruit tree plantations.
References:The first written record of church in Danmark locality date back to the year 1291. Close to the church are several stones with a Christian text and cross inscribed. The oldest parts of the present red-brick church are from the 1300s. In the late 1400s the church was enlarged to the appearance it has today. The church has been modified both internally and externally several times, among other things after the fires in 1699 and 1889. There are lot of well-preserved mural paintings in the walls.