Adso of Montier-en-Der
Adso of Montier-en-Der (Latin: Adso Dervensis; 910/920 – 992) was abbot of the Benedictine monastery of Montier-en-Der in France, and died on a pilgrimage to Jerusalem. Biographical information on Adso comes mainly from one single source and has come under question, but the traditional biography depicts him as an abbot who enacted important monastic reform, as a scholar, and as a writer of five hagiographies.