(b 8th century; d after 837). Churchman and liturgist. Born a Goth in Septimania, he is first documented in 808 as chancellor to Louis the Pious, who had been placed on the throne of Aquitania by his father Charlemagne. When Louis became emperor after the death of Charlemagne in 814, he brought Helisachar to Aachen with him to continue in the role of chancellor. He served in that capacity until about 817, remaining in close contact with the court of Louis for the rest of his career except for a period of disfavour from 830 to 833. Though a canon and not a monk, he was named abbot of St Aubin, Angers, and also of Saint Riquier (822–37).
Louis took an active interest in ecclesiastical matters including the liturgy, and Helisachar, along with his better-known associate Benedict of Aniane (d 821), served him as adviser in that regard. Helisachar was the author of a preface and supplement to Alcuin's epistolary, and the author of a letter (written probably at Angers between 819 and 822) to Archbishop Nibridius of Narbonne, in which he described his composition of an Office antiphoner. Like Amalarius of Metz after him, Helisachar was scandalized at the differences between the Roman and Frankish Office books (not those of the Mass, it should be noted), and sought to compile an antiphoner that would presumably serve as a model for the Carolingian realm. He was particularly keen to select verses that would correspond properly with the respond of the responsories; much of the difficulty with inappropriate verses was no doubt caused by the Frankish practice of returning after the verse to some midway point in the response rather than to its beginning, as was the custom in Rome. It has not been possible to reconstruct Helisachar's antiphoner as it has in the case of Amalarius.
E. Bishop: ‘Ein Schreiben des Abts Helisachar’, Neues Archiv der Gesellschaft für ältere deutsche Geschichtskunde, xi (1911)
D.G. Morin: ‘Une rédaction inédite de la préface au supplément du Comes d’Alcuin’, Revue bénédictine, xxix (1912), 341–8
E. Bishop: ‘A Letter of Abbot Helisachar’, Liturgica historica (Oxford,1918), 333–48
M. Huglo: ‘Les remaniements de l’antiphonaire grégorien au IXe siècle: Hélisachar, Agobard, Amalaire’, Culto cristiano, politica imperiale carolingia: Todi 1977, 87–120
M. Huglo: ‘Trois livres manuscrits présentés par Helisachar’, Revue bénédictine, xcix (1989), 272–85
M. Huglo: ‘D'Helisachar à abbon de Fleury’, Revue bénédictine, civ (1994), 204–30
K. Levy: ‘Abbot Helisachar’s Antiphoner’, JAMS, xlviii (1995), 171–86
JAMES W. McKINNON