In the 4th century BCE, Celtic tribes immigrated to the territories around the river Rába and defeated the Illyrian people who had been living there, but the Illyrians managed to assimilate the Celts, who adopted their language.^[2] Around 300 BCE they waged successful war against the Scythians. These peoples merged with each other through time. In the 290s and 280s BCE, the Celtic people who were migrating towards the Balkan Peninsula passed through Transdanubia but some of the tribes settled on the territory.^[3] Following 279 BCE, the Scordisci (a Celtic tribe), who had been defeated at Delphi, settled at the confluence of the rivers Sava and Danube and they extended their rule over the southern parts of Transdanubia.^[3] Around that time, the northern parts of Transdanubia were ruled by the Taurisci (also a Celtic tribe) and by 230 BCE, Celtic people (the people of the La Tène culture) had occupied gradually the whole territory of the Great Hungarian Plain.^[3] Between 150 and 100 BCE, a new Celtic tribe, the Boii moved to the Carpathian Basin and they occupied the northern and northeastern parts of the territory (mainly the territory of present Slovakia).^[3] Southern Transdanubia was controlled by the most powerful Celtic tribe, the Scordisci, who were resisted from the east by the Dacians.^[4] The Dacians were dominated by the Celts and couldn't engage in politics until the 1st century BCE, when the tribes were united by Burebista.^[5] Dacia subdued the Scordisci, Taurisci and Boii, however Burebista died shortly after and the centralized power collapsed.^[4]