The municipality of Kneževo was also inhabited in ancient times, probably during the Neolithic period. It is clear that this area was inhabited by people of Illyrian origin, which later mixed with the Celts and other immigrants, including Slavic tribes. Among Roman finds are the remains of an old Christian basilica churches in the villages of Imljani and Javorani, indicating a significant degree of population and cultural development.
Roman bricks were discovered below the road which led from Banja Luka to Kneževo and further on, in the villages Kostići and Rađići, which indicates the existence of watch houses along the Roman roads. There are also traces of stećak tombstones – upright stone slabs decorated with paintings and reliefs (village Baština, Mramorije in Kobilja and Barice in village Borak).