Heinrich Kramer (c. 1430 – 1505), also known under the Latinized name Henricus Institor, was a German churchman and inquisitor. With his widely distributed book Malleus Maleficarum (1487), which describes witchcraft and endorses detailed processes for the extermination of witches, he was instrumental in establishing the period of witch trials in the early modern period.
Born in Sélestat, Alsace, he joined the Dominican Order at an early age and while still a young man was appointed Prior of the Dominican house of his native town.
At some date before 1474 he was appointed Inquisitor for the Tyrol, Salzburg, Bohemia and Moravia. His eloquence in the pulpit and tireless activity received recognition at Rome and he was the right-hand man of the Archbishop of Salzburg.
Kramer wrote the text of the papal bull Summis desiderantes which Pope Innocent VIII published in 1484. The bull acknowledges the existence of witches and explicitly empowers the inquisition to prosecute witches and sorcerers. This bull was incoroporated in Kramer's book Malleus Maleficarum (literally "The Hammer of Witches") which was first published in 1487 and became very influential in endorsing the fight against witches.
Kramer failed in his attempt to obtain endorsement for this work from the top theologians of the Inquisition at the Faculty of Cologne, and they condemned the book as recommending unethical and illegal procedures, as well as being inconsistent with Catholic doctrines of demonology.
In 1495 he was summoned to Venice to give public lectures, which were very popular. In 1500 he was empowered to proceed against the Waldensians and Picards.
He died in either Brünn or Olmütz, in Moravia, in 1505.
- Malleus Maleficarum
- Several Discourses and Various Sermons upon the Most Holy Sacrament of the Eucharist, Nuremberg, 1496
- A Tract Confuting the Errors of Master Antonio degli Roselli, Venice, 1499
- The Shield of Defence of the Holy Roman Church Against the Picards and Waldenses, c. 1500