It was believed that the barbarian could be culturally assimilated. Through intermarriage with the local Bantus, the herders were gradually assimilated culturally, linguistically and racially. They merged with the local Romanised population that was gradually assimilated. The Polabian Slavs were gradually assimilated by the Germans. Over the centuries, they were fully assimilated into the Hungarian population. The vast majority have been largely assimilated. Conversely, some Slavs were assimilated into other populations. Roman culture was fully assimilated by the local population. Since the 1960s, mainstream society has assimilated many aspects of hippie culture. They often assimilated into the Tibetan population. Historically, Polish-Americans have assimilated very quickly to American society. Some have also been assimilated by other populations or have undergone many other changes. These languages were then assimilated into another language, mostly Russian. They were assimilated to the Portuguese population. With Rome's northwards expansion, Padua was gradually assimilated into the Roman Republic.