The Bastarnae first came into conflict with the Romans during the 1st century BC when, in alliance with Dacians and Sarmatians, they unsuccessfully resisted Roman expansion into Moesia and Pannonia. Later, they appear to have maintained friendly relations with the Roman Empire during the first two centuries AD. This changed c. 180, when the Bastarnae are recorded as participants in an invasion of Roman territory, once again in alliance with Sarmatian and Dacian elements. In the mid-3rd century, the Bastarnae were part of a Gothic-led grand coalition of lower Danube tribes that repeatedly invaded the Balkan provinces of the Roman Empire.