Albert of Brandenburg, the archbishop of Mainz, sponsors a sale of indulgences—the remission of temporal punishments for sins committed and confessed to a priest—in 1517 to pay the pope for his appointment to Mainz and for the construction of Saint Peter's in Rome.

He selects Dominican friar Johann Tetzel to preach the indulgences and collect the revenues.

Upon Tetzel’s arrival in Saxony, an indignant Martin Luther writes to his bishop, Albrecht von Brandenburg, protesting the sale of indulgences, and encloses in his letter a copy of his "Disputation of Martin Luther on the Power and Efficacy of Indulgences", which will come to be known as the Ninety-five Theses.

Although some of the theses directly criticize papal policies, Luther presents them as tentative objections for discussion.