Around January of 897, Pope Stephen VI ordered that the corpse of his predecessor Pope Formosus be removed from its tomb and brought to the papal court for judgement. At the proceedings, the body of Formosus was seated on a throne while his successor, Pope Stephen, read the charges against him
Formosus was accused of transmigrating sees (moving to be Bishop in another seat), of perjury, and of serving as a Bishop while actually a layman. Stephen had the corpse stripped of its papal vestments, cut off the three fingers of his right hand used for benedictions, and declared all of his acts and ordinations (including his ordination of Stephen himself as Bishop of Anagni) invalid. The body was initially interred in a graveyard for foreigners, only to be dug up once again, tied to weights, and cast into the Tiber River.
Rumors circulated that Formosus’ body, after washing up on the banks of the Tiber, had begun to perform miracles. A public uprising led to Stephen being deposed and imprisoned. While in prison, in July or August of 897, he was strangled.
In November 897, Pope Theodore II convened a synod that annulled the trial, rehabilitated Formosus, and ordered that his body, which had been recovered from the Tiber, be reburied in Saint Peter’s Basilica in pontifical vestments.