Pope Stephen III served as the head of the Roman Catholic Church from 768 to 772. He was the first pope to be elected after the death of Pope Stephen II, and his papacy was marked by efforts to strengthen the church's influence in the political affairs of Europe, particularly in relation to the Frankish kingdom. During his papacy, Stephen III worked closely with Charlemagne, the King of the Franks, to promote the church's interests. He also focused on addressing issues within the church, including the need for reform and the establishment of a more organized ecclesiastical structure.