The Rector of Harrow at this time was one Elias of Dereham (who was also involved in the building of Salisbury Cathedral) and it was he who appointed the first vicar, John de Holtune, about the year 1236.

The second was founded by the then rector, William de Bosco, ‘‘to the honour of God and the Blessed Virgin Mary’’,[citation needed] and was in the present building.

The small room, still there at the top of the staircase, contains evidence of Norman work, traces of colour decoration on the roof beams and a carved niche.

[4] By 1450, the present clerestory windows, the nave and transept roofs, in the chancel and the upper stages of the tower with its famous spire, had been constructed.

A proposal in 1893 to build an organ at the south side of the chancel was abandoned when three Norman windows were uncovered, still showing decoration on the splays.

[5] The chancel roof, which had been renewed in the 18th century, was decorated in 1972 by Campbell Smith & Co.[citation needed] There are thirteen ancient brasses in the church, mostly badly mutilated.

The cope, to be seen in the North transept, was made for the 900th anniversary of the laying of the foundation stone, and the embroidered designs on this were copied from the mutilated brass of John Byrkhede in the chancel.

[citation needed] The brass to John Lyon, founder of Harrow School, and his wife, Joan, is on the wall of the nave, near his grave by the lectern.