The legacy of the Roman Empire has been varied and significant. The Roman Empire, built upon the legacy of other cultures, has had long-lasting influence with broad geographical reach on a great range of cultural aspects, including state institutions, law, values, religious beliefs, technological advances, engineering, and language.
This legacy survived the demise of the empire (5th century AD in the West, and 15th century AD in the East) and went on to shape other civilisations, a process which continues. Rome was the civitas (reflected in the etymology of the word "civilisation") and connected with the actual western civilisation on which subsequent cultures built is the Latin language of ancient Rome, epitomized by the Classical Latin used in Latin literature, which evolved during the Middle Ages and remains in use in the Roman Catholic Church as Ecclesiastical Latin. Vulgar Latin, the common tongue used for regular social interactions, evolved simultaneously into Romance languages that still exist today, such as Italian, French, Spanish, Portuguese, Catalan, and Romanian. Although the Western Roman Empire fell in the 5th century AD, the Eastern Roman Empire continued until its conquest by the Ottoman Empire in the 15th century AD and cemented the Greek language in many parts of the Eastern Mediterranean even after the Early Muslim conquests of the 7th century AD. Roman paganism was largely displaced by Roman Catholic Christianity after the 4th century AD and the Christian conversion of Roman emperor Constantine I (r. 306–337 AD). The Christian faith of the late Roman Empire continued to evolve during the Middle Ages and remains a major facet of the religion and the psyche of the modern Western world.
