Derventa fair is an economic and entertaining manifestation of an international character, it is one of the oldest manifestations in Bosnia and Herzegovina as well as one of the largest fairs in the Former Yugoslavia. It is held every year on the Orthodox holiday of the Dormition, the 28^th of August, and its tradition dates back to 1851.

With its numerous and various contents, the Fair attracts numerous visitors and tourists, first of all from the area of Derventa municipality and neighboring municipalities Prnjavor, Brod, Srbac, Modriča and Doboj, but also from the entire Bosnia and Herzegovina, even wider. From its establishment the Fair has been the most significant event in Derventa, and it also served as a unique opportunity for gathering and exchanging information, business negotiation, meeting young people, “presenting“ young boys and girls ready to be married.

According to the historical data and traditional tales, the beginning of the fair is related to the beginning of the construction of the Orthodox Church of The Dormition of the Holy Mother of God in Derventa. The building of the church, as the response to an appeal of the Orthodox believers, was approved with firman by the Ottoman Sultan Abdul Medžid I in 1851. The believers marked the beginning of the church construction in the same year with folk feast- i.e. the first fair. Construction of the church dedicated to the Dormition holiday, was finished in 1855, while the church was consecrated in 1862.  During the Ottoman period The Fair was held in the churchyard. 

The Fair gained on its significance during Austro-Hungarian administration, when it was one of the biggest fairs in Bosnia and Herzegovina. It was named The Annual Fair, and was celebrated from 28^th till 31^st of August. The Fair was significant for livestock trade, as well as for other agricultural and handicraft goods trade. In that period the venue of the fair was moved from churchyard to the other river bank of the Ukrina River- to the fairground, where it has been held till nowadays.

The fair organization has been interrupted during the wars in the 20^th century, while after the World War II it was modestly marked.

From the mid-20^th century, apart from economic one, the fair gains the entertaining character as well. It was enriched by catering services, the amusement park, games of chance and other contents. Along the Fair, as a central event, economic, sports, cultural and artistic manifestations tend to be organized.

The Orthodox holiday of The Dormition was proclaimed as the Saint Patron's Day of Derventa municipality in 1992, while the Fair together with other contents was named The Dormition gathering. During the gathering, the Saint Patron's day of the Municipality is celebrated, prominent persons and institutions are awarded with honors, the fair of trade and tourism is held, catfish pot and fish pot preparation competitions, as well as beach volleyball and handball tournaments, motorbike days, music concerts and other manifestations are organized.