Pope Formosus, born in the year eight hundred sixteen, served as the pope and ruler of the Papal States from six October eight hundred ninety-one until his death on four April eight hundred ninety-six. His papacy was marked by significant turmoil, as he navigated complex power struggles involving the Patriarchate of Constantinople, the Kingdom of West Francia, and the Holy Roman Empire.
Formosus's political alliances were contentious; he notably sided with Arnulf of Carinthia against Lambert of Spoleto. This decision would later haunt his legacy, culminating in the infamous Cadaver Synod, where his remains were exhumed and put on trial. His actions during his papacy led to a perception of him as having abandoned the ideals of the Church, particularly due to his departure from the diocese in Portus to pursue personal ambitions in Rome.
The aftermath of his reign left a controversial legacy that preoccupied several of his immediate successors. They grappled with the implications of his decisions and the judgment passed by Stephen VI, who criticized Formosus for assuming an elevated role while still holding another position. This scrutiny ultimately led to the unique circumstance that no subsequent pope has ever adopted the name Formosus.