Sites and some data suggest that this area was inhabited from time immemorial. After the fall of the Roman Empire, the area between the rivers Una and Vrbas were inhabited by Slavic tribes.
From the year 930, this region has witnessed a great rise. Then, the great city of Dubica was founded which covered the villages Draksenic, Medjedja, Demirovac, with the centre in today’s village of Donja Gradina. The city flourished until 1242, when it was destroyed by the Mongols led by Batu Khan.
Dubica was first mentioned in history in 1258 under the name “Kastrum” as a large crafts and trade settlement. The town name Dubica comes from the Slavic word ‘dub’ meaning oak.
With the arrival of Turkey in 1538, Dubica became a very significant fortification situated between two empires (Ottoman and Austro-Hungarian).