Immediately west of the Cecil Chapel separated by an oaken screen, is the Warrior Chapel designed by Sir Thomas G Jackson who lived at Eagle House. It was built in 1920 and as the Cecil Chapel was used as the choir vestry, it necessitated the building of a new choir vestry to the south and this in turn was enlarged eastwards to provide the clergy vestry in 1950. The Warrior Chapel is dedicated to the men of Wimbledon who gave their lives in the two World Wars. Inset in the oak panelled walls are the individual bronze tablets bearing the name and rank of each. Prominently in the centre are three VC's, two from the first World War and from the second World War, Ian Willoughby Bazalgette, Squadron Leader, killed in air operations in 1944 aged 25 years. His forbear, Sir Joseph William has his memorial tablet on the north wall of the chancel.
Underneath the tablets of the VC's is a low-side window which was revealed in 1919 during the building of the Warrior Chapel. This was originally an outside wall and it appears to date from the rebuilding of the chancel in the late thirteenth century at a time when the floor of the church was nearly two feet lower than it is today. It is thought that the window with its vertical iron bar may have been used to hear confessions and administer the Sacrament to diseased people forced to remain outside. This led to it often being referred to as a leper window. Such windows have also been called 'lychnoscopes' either because the Pascal lights might be watched through them or because they were used for lights to scare away demons from the graves. Another (more prosaic) theory was simply that it provided ventilation from the burning incense within.