The Early Middle Ages (circa 500-1000 AD) followed the fall of the Roman Empire, marked by the rise of feudalism and the spread of Christianity. This period saw the establishment of various kingdoms, such as the Franks under Charlemagne, who united much of Western Europe. The economy was primarily agrarian, and learning was largely preserved by monasteries. The Late Middle Ages (circa 1000-1500 AD) experienced significant changes, including the growth of towns and trade, leading to the rise of a merchant class. This era also witnessed the Crusades, the Black Death, and the beginning of the Renaissance, which shifted focus towards humanism and the arts, transforming European society.