The aisled nave has six bays, the westernmost one forming a kind of narthex with organ tribune. There is no real transept, the "crossing" bay being marked by the presence of a heavy tower to the north. In the chevet on straight bay leads to a trapezoidal hemicycle surrounded by an ambulatory and three chapels. Very slender supports stand in the mouths of the chapels.
The church, dedicated to Saint Eusèbe, bishop of Verceil, originally formed part of a monastery built outside the city walls by Bishop Palladius (623-659) who had the apse decorated with a splendid mosaic and who was eventually buried there (as were several of his successors).
Destroyed during the period of Viking attacks the church, now served by canons, was reestablished in the eleventh century. The establishment formed the center of the bourg Saint-Eusèbe.
Major rebuilding took place in the second half of 12th century, starting in the chevet.
There was a fire in 1216 which may have led to the reconstruction of the upper nave.
The old chevet collapsed in 1530: the new chevet constitutes a wonderful conflation of Late Gothic design with "Renaissance" articulation. Plans to demolish the old tower and rebuild the nave were fortunately not accomplished.
Reference to Sens (especially the triforum) and S-Germain-des-Prés
Porée, Charles, "Saint-Eusèbe," Congrès archéologique d'Avallon, 1907, 188-193
Vallery-Radot, Charles, "L'Eglise Saint-Eusèbe d'Auxerre," Congrès archéologique, 116, 1958, 87-96.
Branner, Robert, Burgundian Gothic, London, 1960, 31.