Martin Luther was a priest who was against the an churches actions in Wittenburg on selling indulgences. In fact he was so agaisnt it he complained about it in ninety-five theses. The Ninety-five Theses contained the churches pratices and most importantly the fact that they were selling indulgences. Luther's complaints had bothered many German bishops as well as Pope Leo X. Martin was called a "heretic" and was excommunicated. Later Luther's ideas led to the split in the Roman Catholic Church. Those who took Luther's side and protested against the church became known as Prostestants.