English biographer of St. Anselm and historian whose accounts are a uniquely accurate and credible portrait of the 12th-century monastic community at Canterbury.

Born into a wealthy family that was impoverished by the Norman conquest, Edmer was raised at Christ Church, Canterbury, where he lived as a monk until 1093. After the accession of Anselm to the archbishopric in 1093, Edmer became a member of his household, probably acting as secretary and chaplain. Until Anselm's death in 1109, Edmer accompanied him on extensive travels to Rome, Cluny, and the councils of Bari (1098) and the Vatican (1099). Between 1109 and 1114 he remained relatively inactive, but he returned to Canterbury under Archbishop Ralph in 1119.

His two greatest works are a six-book Historia novorum in Anglia (c. 1115), an account of events in England as seen from Canterbury, stressing Anselm's role in the Investiture Controversy between the political and clerical authorities, and the Vita Anselmi (c. 1124), an authoritative biography of Anselm's private life. Edmer's importance in historiography rests on his powers of critical observation and description, a novel emphasis on psychological factors in biographical writing, and a clear recognition of the implications of the Investiture Controversy.