In 1515, Pope Leo X granted the sale of a new indulgence for the Archbishopric of
Magdeburg to raise funds for the ongoing construction of St. Peter's Basilica in Rome. Prior to this, the Archbishop of Magdeburg, Albrecht von Brandenburg, had taken out a huge debt with the Fugger bank in
Augsburg to pay for his appointment and dispensation fees. As security for this debt he signed a deal that ensured at least half the income from the St. Peter's indulgence would go straight to the bank. At the archbishop's behest, the Dominican monk Johann Tetzel travelled around the archdiocese to swell the indulgence chest, using promises, threats and the couplet "a soon as a coin in the coffer rings, the soul from purgatory springs."
Luther criticised Tetzel's sermons and fund-raising tactics from an early stage. He feared the machinations of the indulgence preachers would encourage irrational beliefs. On 31 October 1517, he published his 95 theses, condemning the corrupt practice of indulgences and raising the matter for discussion. One of the recipients was Archbishop Albrecht von Brandenburg, who passed them on to Rome. To Luther's surprise, his theses circulated widely and met with much success. They are now regarded as the trigger for the Protestant Reformation.
