MARIO of AVENTICUM (of LAUSANNE). - Bishop of Avenches (western Switzerland) from 574 to 594, he transferred his episcopal see to Lausanne (cf. L. Duchesne, Fastes épiscopaux de l'ancienne Gaule, III, Paris 1915, pp. 22, 219-20).
He wrote his Chronicle as a continuator of that of Prosper, covering the years 455-581, based on Italian consular fasti and on yellowed parchments. It is important for the information it provides regarding local history. It is preserved only in cod. Mus. Brit. 1697 (10th cent.).
Bibl.: Edition: Th. Mommsen, Chronica minora, II, in MGH, Ant. antiquiss., XI, p. 227 sq. (with notes on M.'s life). Studies: M. Busson, Histoire des évêques de Genève, Geneva 1906, pp. 176-90; Eltester, s. V. in Pauly-Wissowa, XIV, II, p. 182 sq.