Gregorian chant
Gregorian chant appeared in a remarkably uniform state across Europe within a short time. Charlemagne, once elevated to Holy Roman Emperor, aggressively spread Gregorian chant throughout his empire to consolidate religious and secular power, requiring the clergy to use the new repertory on pain of death. From English and German sources, Gregorian chant spread north to Scandinavia, Iceland and Finland. In 885, Pope Stephen V banned the Slavonic liturgy, leading to the ascendancy of Gregorian chant in Eastern Catholic lands including Poland, Moravia and Slovakia.