A friar of the Augustinians, Martin Luther, was a leading figure in this century. He was exceedingly bothered by the corruption and abuses of the Catholic Church, who was selling indulgences and remissions as atonements for sins. The 95 Theses, which he published in 1517, attacked these practices among others, and became extremely controversial. Three pamphlets which he published in 1520 also expressed his beliefs regarding the liberty of Christian conscience, the priesthood of all believers and a Church supported by the State.

The ideas put forth by Martin Luther had avid listeners in Germany, and as these doctrines were undermining the Church' s authority, Pope Leo X issued a bull condemning Luther and his works. Luther was excommunicated and outlawed after burning the bull and not recanting at the Diet of Worms in 1521. However, an Elector of Saxony by the name of Frederick the Wise provided refuge for the reformist in Wartburg Castle where he was safe to start translating the Bible into German.

Luther's s widely disseminated ideas, however were in many cases combined with other ends. Many princes and landlords used it as an excuse to gain vast church lands and even the peasants tried justifying their revolt with Luther's doctrines.

In the early 16th Century the German population had continued to grow, causing land prices to increase considerably. Landlords were intent on reintroducing feudal type labour on their lands, triggering a profound resentment on the peasant's part. The Peasants' Revolt in the Black Forest took place between 1524 and 1526 and was said to have involved approximately 250,000 people.

Lutheranism was well established in North Germany by the mid-16th Century, but in the South Catholicism continued to exist and even began to flourish with the Jesuits in what was called the Counter-Reformation, during which many Germans were won back to Catholicism.