Romance languages are the continuation of Vulgar Latin, the popular and colloquial sociolect of Latin spoken by soldiers, settlers and merchants of the Roman Empire, as distinguished from the classical form of the language spoken by the Roman upper classes, the form in which the language was generally written. Between 350 BC and AD 150, the expansion of the Empire, together with its administrative and educational policies, made Latin the dominant native language in continental Western Europe. Latin also exerted a strong influence in southeastern Britain, the Roman province of Africa, and the Balkans north of the Jireček Line.