Due to the land uplift, which is around 50 cm per century in this area, the islands have changed both in size and number. Today there are approximately 1 600 islands and islets. It is assumed that Houtskär has had a Swedish settlement since the 13th century.
The parish of Houtskär is mentioned in 1554, but until 1867 Houtskär was a part of the parish of Korpo. The present red wooden church, Saint Mary’s church, located in Näsby, was built in 1703. The traditional livelihood for the inhabitants of Houtskär has been fishing and shipping. At the end of the 19th century the population was around 2000 people. Thanks to the fishing, the people in the archipelago survived the difficult famine of 1867-68 better than the people on the mainland, who suffered largely because of the poor harvests.