770 – 24 January 817) was Bishop of Rome and ruler of the Papal States from June 816 to his death in 817.Stephen belonged to a noble Roman family.
He was consecrated pope on or about 22 June 816.
The following October, he crowned Louis the Pious, Holy Roman Emperor at Rheims, and persuaded the emperor to release some Roman political prisoners he held in custody.
He returned to Rome, by way of Ravenna, sometime in November and died the following January.