Santok is mentioned in the 12th century as "barbican and key" (Latin: clavem et terris custodiam) to the Polish kingdom at the border with the Duchy of Pomerania in the Gesta principum Polonorum chronicle by Gallus Anonymus.

Re-established by Bolesław I the Brave in the days of the medieval Piast dynasty, Santok became an important border fortress of Greater Poland and seat of a castellany.

During the 13th century however, the strategically important hill fort became the object of claims raised by the Ascanian margraves of Brandenburg, who intended to enlarge their territories in the Neumark region east of the Oder river.

Upon the marriage of Margrave Conrad of Brandenburg-Stendal with Constance, daughter of the deceased Duke Przemysł I of Greater Poland, in 1260, Santok passed to the margraviate as part of her dowry.

One part belonged to the property complex of Frederick Henry, Margrave of Brandenburg-Schwedt and the remainder was owned by the Schöning noble family.