Some Roman authorities consider them a Thracian stock, because of their admixture with an older Thraco-Illyrian population. As early as 175 BC they came into collision with the Romans by assisting Perseus, king of Macedonia; and after Macedonia became a Roman province they were for many years engaged in hostilities with them.
In 135 BC they were defeated by Cosconius in Thrace. In 118 BC, according to a memorial stone discovered near Thessalonic, Sextus Pompeius, probably the grandfather of te~ triumvir, was slain fighting against them near Stobi. In 114 BC they surprised and destroyed the army of Gaius Porcius Cato in the Serbian mountains, but were defeated by Minucius Rufus in 107 BC.
Nevertheless, they still from time to time gave trouble to the Roman governors of Macedonia, whose territory they invaded in combination with the Maedi and Dardani. They even advanced as far as Delphi and plundered the temple; but Lucius Cornelius Scipio Asiaticus finally overcame them in 88 BC and drove them across the Danube. In Strabo's time they had been expelled from the valley of the Danube by the Dacians.