Roman martyrs. Originally they were culted separately. Tiburtius is known from an epitaph by Damasus and he is mentioned in the early sacramentaries and pilgrim guides. He was buried on the Via Lavicana (3 miles from Rome) at a place called The Two Laurels. A church was later built here. Susanna, however, suffered at ‘The Two Houses beside the Baths of Diocletian’: the church here, formerly called titulus Gaii, was renamed the church of St Susanna in the 6th century. A Legend of Susanna was written round the topographical data of the genuine martyrology entry, but invented, it would seem, various people and episodes with Pope Caius also having a part in the story. The reason for the common celebration of Tiburtius and Susanna together appears to be quite simply that their names are found on the same day in the martyrology. They did not necessarily suffer in the same year or even the same persecution. Feast: 11 August.
C.M.H., pp. 434–5; L. Duchesne in Mélanges d'archéologie et d'histoire, xxxvi (1916), 27–42; J. P. Kirsch, ‘Die Martyrer der Katachombe ad duas lauras’, Ehrengabe deutscher Wissenschaft dargeboten von Katholischen Gelehrten (1920), pp. 577–601; AA.SS. Aug. II (1735), 613–32.