The former Benedictine abbey church of St Germain in Auxerre, France, now comprises the remains of a Carolingian crypt, a Gothic choir and transepts, and the four eastern bays of the nave; the western nave bays and the Carolingian westwork were destroyed in the early 19th century. A detached 12th-century bell-tower also survives. The medieval history of the abbey is dominated by the cult of St Germanus, the second bishop of Auxerre (reg 418–48), who was born in the town and was an important figure in the Church’s campaign against the Pelagian heresy.
St Germanus’s tomb lay below the level of the main apse of the Merovingian church built c. 493–533 by Queen Clotilde, wife of Clovis I (reg 481–511). Between 841 and 859 Conrad, Comte d’Auxerre, the uncle of Emperor Charles the Bald, decided to enhance the structure, and a contemporary description mentions the ‘admirable unit of crypts’ organized around the semi-subterranean confessio containing Germanus’s remains. In this form of ‘outer crypt’ the confessio formed the nucleus of a small aisled, vaulted chamber surrounded by a corridor leading to small chapels in echelon. Attached to the crypt at the east was a circular oratory that was part of the same building programme. This elaborate arrangement, which provided access to the tomb on important feast days, reflects the growing importance of the cult of relics in the Carolingian period....