HISTORY OF MUSIC By Clarity 380 Christianity, official religion of Rome 476 German invasión of Rome. Start of the Middle Age Period: 800 to 900 IX Century -Gregory the Great compiles plainsong -Birth of liturgical polyphonyç -Birth of secular vocal music Period: 900 to 1000 X Century -Start of Romanesque style Period: 1200 to 1300 XIII Century -Start of Gothic style -Cantigas de Santa Maria, Alfonso X the Wise 1473 Fall of Constantinople 1492 Discovery of America. End of the Middle Age