Pope Formosus
In January 897, Pope Stephen VI held what is known as the Cadaver Synod. He had the body of Pope Formosus, the rival of his ally, Lambert of Spoleto, exhumed and tried for "perjury, violating the canons prohibiting the translation of bishops, and coveting the papacy." After finding him guilty, the synod annulled all of Formosus' acts and ordinations. Formosus' body was reburied in a common grave, and then thrown in the river Tiber. Supporters of Formosus rebelled, and seven months after the synod, Stephen VI was deposed, and died soon after in prison.