A modest man of great accomplishments, Walahfrid was a fine poet, teacher, abbot, gardener, liturgist, and diplomat. His personal notebook reveals that he loved arithmetic and astronomy. For a decade, he tutored Carolus iunior, youngest son of Judith and Ludwig der Fromme, who became emperor Charles the Bald. On two occasions, Walahfrid found and transcribed formulae and explanations of time series, often correcting them. By identifying Walahfrid's sources and scripts, Professor Stevens is able to trace his life and scholarship, as they relate to Carolingian politics and schools in the first half of ninth-century Europe.