Adeodatus II
Adeodatus · 672 – 676
A Benedictine monk-pope who governed quietly, supported his monastery, and is credited with first using the dating phrase 'anno Domini.'
Adeodatus was a Roman monk from the monastery of St. Erasmus on the Caelian Hill. His pontificate was relatively peaceful. He is noted for his generosity, particularly toward his own monastic community, and for maintaining the Church's administration without major controversy. He is sometimes credited with being the first pope to use leaden seals (bullae) on papal documents and with popularizing the 'anno Domini' dating system in papal correspondence.
A Quiet Pope
Not every pope needs to fight an emperor or condemn a heresy. Adeodatus governed during a calm stretch and used the time to keep things running smoothly. He repaired monasteries, maintained the bureaucracy, and left the Church in good order for his successor. That kind of steady, unglamorous work holds institutions together.