Doboj is located at elevation of 146 meters, on the left bank of the Bosnia River, where rivers of Usora and Spreca join. Archaeological finds testify on human settlements on the present day Doboj locality since the Early Stone Age – Paleolithic, through the Lower Stone Age /Neolithic/, Copper, Bronze and Iron ages, until the present. Thanks to its suitable geographic location, Doboj has always been an important crossroad on the significant road from Pannonia and the Middle Europe to the Adriatic and the Mediterranean, on directions from the west to the east. Doboj has thus always been a target for various invading raids, conquered by the Romans in the last century BC, who respected the significance of this crossroad, in the 2nd century AD built a road paved by stone blocks. In the 1st century AD Romans constructed the fortified settlement called Castrum which had outstanding military strategic significance, at the junction of the Usora river with the Bosnia River. Ruins of the Roman Castrum are visible even today, although poorly researched. First inhabitants settled around the Roman Castrum, and many centuries after Romans left, the settlement was created in the 13th century, on the locality of the present Gradina, how locals of Doboj call the fortification on the stone hill across the spot where the Spreca river joins the Bosnia river. This significant fortified stronghold dominated the whole area through the long history of this region.

The oldest, up to now found written document about Doboj dates from 1415, when the Dubrovnik merchants wrote to the Hungarian King Sigismund, whose army was invading through the valley of the Bosnia river, saying that his army is located “in Uxora suptus castrum Doboy” (in Usora, beneath the Doboj fortification). The Turkish defter – written document for 1468/69 confirms the timar – land property 3985 akca of the Duke Jovašin who granted Doboj, and the timar of 2555 akca of the certain Stjepan, who granted Doboj. Those two were commanders of the army garrison of soldiers and were granted two small spahiluk /land property/ for the obligation of the military service. This confirms that the Doboj fortification of Gradina, came into the Turkish hands since that year. As by its location the Doboj fortress existed in the border area between the Turkish and the Hungarian administration, Ottomans recognized the protection role of the stronghold, and in 1490 carried out substantial reconstruction works, under supervision of certain builder Ibrahim.

Some 1500 people worked daily on strengthening of its walls, construction of fortified walls and towers, and storage for ammunition and weapons, and army accommodation facilities. Ruins of those facilities are partially visible today. The Doboj fortress was the key point of the whole Bosnia river valley, and the key stronghold against enemy who might arrive from the Hungarian flat lands, so it dominated the main road through the Usora area up to the very heart of the Bosnian Kingdom. Ottomans felt safe here during their rule, until 1697 when the Austrian commander Eugene of Savoy entered into Bosnia with his 6500 soldiers, whom the Ottoman army at the Doboj fort surrendered without resistance. On that occasion the Doboj fortress and the settlement were set aflame. Turks again took the Doboj fort, when Eugene of Savoy left Bosnia, and succeeded to defend and keep it during the Austrian-Turkish wars 1716-1718, although Austro-hungarians reconquered the settlement and burnt it, without success at the Doboj fortification with 1000 soldiers.

At the end of the 18th century the Doboj captain-ship was established, which belonged to the Tesanj authorities and administration. Doboj fortress lost its significance due to the Ottoman invasion direction Budapest and development of the destruction features of weapons, so historical events mostly passed around or by the fortification. Thus the Austrian 20th squadron which was marching in direction Samac-Gracanica-Zvornik was rejected to locations around the town of Doboj by 5-6000 rebels led by Mehmed Vehbi Semsekadic. The battle lasted from 14 August till 06 September, until Austrians received support, so rebels were expelled across the Spreca river to Tesanj.

During the First World War Austrians created the camp at the fortification where prisoners were kept before the exile to the notorious camps. According to some documents, there were around 45000 prisoners detained there, and there is also an interesting fact that Ivo Andric was prisoner here for some time as well. The last Austrian garrison left the Doboj Fortress in 1851. There was important diversion carried out in Doboj during the Second World War, when 150 German wagon-loads with ammunition for the east Front was detonated. Doboj is liberated on 17 April 1945. Thanks to its good position, after the Second World War Doboj became important crossroad of road and railway traffic, which made it extended rapidly and became regional social and political center and the seat of the county and the region. There are no reliable data about the name of Doboj, only some assumptions that the name comes from the origin of the word “boj”, meaning warfare or battlefield, or the other which means load of clay mixed with straw that is used for construction of thick defensive walls. There are no scientifically attested data, as there are no written documents about the life of settlement at the present day Doboj before Ottomans conquered this area. Nowadays at the Doboj fortress the rich cultural life of the town is performed, and many romantic couples use the fortification for the festive event of wedding. Within the Doboj fort there is the amphitheater where concerts and theatrical performances and poet evenings and other cultural events are held. From the old walls of the Doboj fortress visitors enjoy in marvelous panorama of the town and the beautiful surroundings.