Who he was
Stephen was chosen unanimously in St Mary Major's after a priest also named Stephen died only days after his own election, before he could be consecrated; this is why he is counted as both Stephen II and Stephen III. He had been brought up in the Lateran with his brother, the future Pope Paul I. His reign was taken up from the start by the Lombards' push to take Rome.
What he is remembered for
When Constantinople sent no help he crossed the Alps himself, anointed Pepin King of the Franks, and won his promise to defend the Roman Church. Pepin twice forced the Lombard king Aistulf to give way, and handed Ravenna and the cities around it to the pope, which is why Stephen is often counted the first pope to rule a state of his own. He was also remembered for his care of the poor, building hospices for them near St Peter's.
Sources
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