Manipulating the message: letters of Gelasius and Nicholas I on papal authority

Gelasius I (492‒96), bishop of Rome during the problematic period of Odoacer’s replacement as rex Italiae in 493, was greatly concerned with the power of the bishop of Rome. While Gelasius was one of the most significant bishops of the first five hundred years of the Roman church, he is primarily known for his letter to the Byzantine emperor Anastasius in 494. His Epistula 12 introduced the controversial theory of “two powers” or “two swords,” as it came to be known. The idea was taken up in the mid-ninth century by another champion for papal primacy, when Nicholas I (858-67) embedded a quote from Gelasius in his excoriation of the Byzantine emperor Michael III. I examine the use of political rhetoric in ecclesiastical contexts in late antiquity and the early Middle Ages, and the way that extracts from such letters could go on to have a life of their own in canon law. Finally, I measure the historical impact of each letter as a form of soft diplomacy.