Kozkuk is situated on the left bank of the Drina river on the eastern slopes of the Majevica mountain range and lies on the road between Zvornik and Bijeljina.

The surrounding areas of Kozluk were inhabited by various groups throughout ancient and prehistoric times, among them Illyrian and Celtic tribes.

Afterwards they were conquered and ruled for some periods of time by Ostrogoths, Huns and Avars until finally being settled by Slavic speaking people from the 7th century onwards.

These Slavs have since then dominated the Podrinje region and large parts of the Balkans both ethnically and linguistically even though they were ruled by non-Slavic foreigners for long periods of time.

According to another tradition it got its name from a type of wild plant that the people called "kozjim lukom" or "goat's onion" in English.

141 families with 373 male members moved from Sokol, a ruined town and fortress between Krupnje and Ljubovija, to Kozluk.

Their surnames were: Alajbegović, Alispahić, Arapović, Banjanović, Bašić, Čajkić, Ćatić, Dubočanin, Dudaković, Duraković, Delić, Fejzić, Grabovac, Hergić, Hadžialić, Topčagić, Haluga, Harambašić, Hadžimuratović, Hidić, Ibrišević, Isić, Išimović, Jakubović, Kupinić, Marhošević, Mekić, Mešanagić, Mulalić, Mulaibišević, Mutisagić, Palamarević, Pekmezović, Puškarević, Suljagić, Salihagić, Spahić, Šabić, Terzić and Uzunović.

Families which moved to Kozluk at a later point: Brkić, Ekmečić, Hadžialić, Jahić, Mulaosmanović, Muratović, Memišević, Omerhodžić, Omerović and others.

During the time of Austro-Hungarian rule in Bosnia Kozluk was the seat of the municipality, which consisted of the following settlements: Baljkovica Donja, Dugi Dio, Jusići, Kraljevići, Petkovci, Sapna, Vitinica, Šetići, Tršić, Tabanci, Skočić, Roćević, Gornji Šepak and Donji Šepak.

Apostles Peter and Paul was built, whose first priest, Petar Lazarević, was executed in August 1914 in Tuzla on suspicion of involvement in the Sarajevo assassination.

With the formation of the NDH in April 1941 a police station was built and the Ustaše and Croatian Home Guard established a base, which was led by Halim Spahić.

Smaller crews of Croatian Home Guard also operated in the nearby settlements of Tršić and Roćević.

From October 1943 until it finally fell into the hands of the partisans on February 20, 1945, there was constant fighting in the area of Kozluk and its surroundings.