The E. end of the Abbey next received the attention of these architect-abbots.  Commencing at the second bay E. from the tower, John de Hertford (1235-60) almost entirely replaced the Norman and E.E. work of his predecessors by work which merged into a graceful E. Dec.  The work was carried on by his immediate successors, doubtless sadly hindered by the turbulent state of the times.  John de Norton (1260-90) built the S. aisle of the Retro-choir, and part of the Lady-chapel, but his work was supplemented by that of John de Berkhampstead (1291-1302).  John de Marinis (1302-8) removed the feretry and tomb of St. Alban to the position which it occupied until about the time of the Dissolution and spent 820 marks in the erection of a tomb of Purbeck marble.  Hugh de Eversden (1308-26) built the five moulded Dec. bays of the S. aisle, replacing the Norman work, which had given way, and completed the Lady-chapel at the extreme E., thereby greatly increasing the length of the entire building.  There was subsequently, however, for a long period, a passage between the Retro-choir and the Lady-chapel.

Abbot Michael de Mentmore (1335-49) completed the restoration of the S. aisle and repaired the Cloister.  His successor, Thomas de la Mere, paved the W. floor, and no doubt minor restorations were almost continually in progress during the latter half of the fourteenth century; but a new chapter in the story of the Abbey commenced when John de Wheathampsted became abbot (1420-40 and 1451-64).  This celebrated man, during the two periods of his abbacy, hardly rested in his efforts to beautify the Abbey.  It is stated in a Cottonian MS. that this abbot constructed a little chapel near the shrine of St. Alban; this was perhaps the Watching Loft (N. of Saint’s Chapel) in which the keeper of the holy shrine and relics (Custos Feretri) spent much of his time.  John de Wheathampsted also built the tomb of Humphrey, Duke of Gloucester (d. 1447), on the side of the chapel opposite the Watching Loft (a few steps lead down to the coffin); prepared his own tomb W. from that of the duke; built the great Perp. window over the W. porches, now replaced by one Dec. in design, and the nine N. windows of Nave and Ante-Choir; and was probably responsible for the paintings discovered on the choir ceiling, and for many of the embellishments of the Lady-chapel.  Perhaps, however, his fame chiefly rests on the High Altar Screen, which he designed, but which was erected by the thirty-sixth abbot, William Wallingford (1476-84).

There were apparently few important features added to the Abbey, and but little restoration effected during the rule of the last four abbots (1492-1539).  A few brief paragraphs concerning its modern restorations and present appearance must now be added.

Those modern restorations date largely from the middle of last century.  Its condition, internally and externally, was at that time certainly discreditable to everybody concerned in its welfare.  In 1856 a National Committee placed the matter in the hands of Sir Gilbert Scott, under whose direction the building was in part restored; but public funds presently failed and in 1879 the direction of the workers was undertaken by one who had at once the inclination and the funds necessary to its completion—­Lord Grimthorpe.