Kravjek was once one of the more important castles of the Duchy of Carinthia. Its first owners were the Dukes of Spanheim, who managed the castle via their ministeriales. This practice resulted in the castle's first indirect mention in a 1243 record of a legal proceeding, in which a "Friderik castellanus de Weinek" was called as a witness. The castle was next indirectly mentioned in written sources in 1254, when its castellan Rajnboto of Jetrbenšek, ministerialis of Duke Ulrik III, donated two farms and two vineyards to Stična Abbey.
The first direct record of the castle dates from 1256, in an agreement signed by the brothers Ulrik and Phillip of Salzburg, dividing their inheritance. Ulrik received Ljubljana Castle and Kostanjevica Castle, and Phillip took possession of the Carinthian castles at Himmelberg and Wernberg, as well as the castles at Sostro and Kravjek.
- Kos, Dušan. Med gradom in mestom, p. 26
- Jaksch, A. Monumenta historica ducatus Carinthiae, vol. 4, no. 2627, p. 490
- Jaksch, A. Monumenta historica ducatus Carinthiae, vol. 5, no. 246; cf. Mittheilungen des instituts für österreichische Geschchtsforschung, vol. 22. Innsbruck 1901, p. 456.
- Ivan Stopar, Grajske stavbe v osrednji Sloveniji, II. Dolenjska, book III, Porečje Temenice in Mirne, Viharnik, Ljubljana 2002 ISBN 961-6057-34-0