[1] The chancel is Early English Period, but the main structure is in the Late Perpendicular Gothic style, dating from about the reign of Henry VII, and rebuilt in 1620.
It was restored under the direction of Sir George Gilbert Scott when new oak roofs were added, and the old carving, retained wherever possible, or faithfully reproduced.
There are several stained windows, a pulpit of carved alabaster around which runs an elaborate railing of metal work, in which a combination of copper, brass and tin has been used, the whole resting on a stone base.
The celebrated entry of the baptism of Oliver Cromwell occurs in the register of St John's under the date of 1599, and there is a mention, about twenty years later, of his having done penance for some improper conduct.
There is also mention made of the resting within its walls of the body of Mary Queen of Scots on its way from Peterborough Cathedral to Westminster Abbey, to which latter place it was removed by order of her son, James I.