The Dacia of King Burebista (82–44 BCE) stretched from the Black Sea to the source of the river Tisa and from the Balkan Mountains to Bohemia. He was the first king who successfully unified the tribes of the Dacian kingdom, which comprised the area located between the Danube, Tisza, and Dniester rivers, and modern day Romania and Moldova. From 61 BCE onwards Burebista pursued a series of conquests that expanded the Dacian kingdom. The tribes of the Boii and Taurisci were destroyed early in his campaigns, followed by the conquest of the Bastarnae and probably the Scordisci peoples. He led raids throughout Thrace, Macedonia, and Illyria. From 55 BCE the Greek cities on the west coast of the Black Sea were conquered one after another. These campaigns inevitably culminated in conflict with Rome in 48 BCE, at which point Burebista gave his support to Pompey. This in turn made him an enemy to Caesar, who decided to start a campaign against Dacia. In 53 BCE, Burebista was murdered, and the kingdom was divided into four (later five) parts under separate rulers.