Södertuna Castle just outside Gnesta in Södermanland is known since the 1300s with Knight Karl Nilsson (Niklisson) as its first owner. Nilsson was killed by “the richest Swede of all time” Bo Jonsson Grip in 1381 inside what is today Riddarholmen Church in central Stockholm. The original house was an old fortified manor called Wad (a place where one could wade).
During the time of the Thirty Years’ War (1618-1648) the Swedish Crown needed money to support its armies. Many noblemen were therefore awarded manors and land instead of money for their efforts.
In 1646, during the reign of Queen Kristina, Claes Stiernsköld acquired Wad through a trade with the Crown. Stiernsköld already owned nearby Tuna. Following the deal, Tuna was named Norrtuna and Wad was named Södertuna (north and south Tuna).
Following Stiernsköld’s death in 1665 the estate passed to his son-in-law Gustaf Adolf Sparre who sold it to Governor Erik Lovisin in 1676. It was during the 100 year reign of the Lovisins at Södertuna that the old Medieval manor was transformed to the castle, with a few changes and additions of course, we see today.
In 1891, Ebba von Hallwyl was given the castle from her grandmother Johanna Kempe. Ebba was married to Wilhelm von Eckermann. They commissioned Isac Gustav Clason to modernise both the interior and exterior of the house.
The von Eckermann family sold the castle and the park in 1985 and it has since then been owned by Södertuna Konferensslott AB. Since 2007, the company has been owned by the Åström family who also own Dufweholm Manor and Gripsholm Inn.