its name is very likely linked to the "breuci" (greek βρεῦκοι), a subtribe of pannonian tribes of the illyrians who migrated to the vicinity of today's brčko from the territories of the yamnaya culture in the 3rd millennium bc. breuci greatly resisted the romans but were conquered in 1st century bc and a lot of them were sold as slaves after their defeat. they started receiving roman citizenship during trajan's rule.