Adriani

7 clues
Eighth-century pope
Pope who sought Charlemagne's aid
Pope during the reign of Charlemagne
Eighth-century pope in office for 23 years
Eighth-century pope with the sixth-longest reign
Pope who reigned for 23 years in the 8th century
Pope with the longest reign between St. Peter and Pius VI (A.D. 67-1799)