Fed up from the poor practice, corruption, and lazy clergy, on October 31, 1517, German monk and Catholic priest Martin Luther nailed his list of complaints of the church door in Wittenberg, Germany formally known as the 95 Theses. Specifically, it criticized the practices and clerical abuses of the Catholic Church such as nepotism, usury, and most importantly, the sale of indulgences. In turn, Luther's actions angered the bishops in and around Wittenberg and all of Germany ultimately causing him to become excommunicated from the church, and he appeared before the Holy Roman Emperor in the Diet of Worms where one noble helped Luther hide from the Emperor once forced to leave the Empire. This didn't stop Luther, he continued to spread his beliefs and teachings all across Europe including the priesthood of all believers which suggested a parishioner did not need a priest to communicate with God, but each individual has their own unique relationship with God. In addition, he spread the idea of which the clergy should not conflict politics, an idea largely favored by German nobles. Overall though, Martin Luther is largely credited with the start of the Protestant Reformation and many of his ideas still linger in modern society.

Martin Luther