The Reformation began in the 1500s when Martin Luther posted his 95 theses criticizing the Catholic Church, establishing the Protestant branch of Christianity. In Lutheran areas of Germany and Scandinavia, hymns replaced most Latin chants in worship, beginning with monophonic hymns and later incorporating polyphony. Calvinist worship in Switzerland, France, and Germany only allowed biblical texts set to metrical psalms, initially monophonic but later with polyphony. Across Europe, Renaissance vocal polyphony developed further from 1420-1600, with composers like Palestrina and Lasso writing multi-voiced masses, motets, and other sacred music that carefully balanced text clarity with complex counterpoint.