The Imperial Challenge Shield (Junior) Competition evolved from the highly prestigious and fiercely contested Earl Robert Trophy inaugurated in 1907. Since 1910, the Competition was conducted annually under the auspices of the National Rifle Association, with the object of encouraging every boy of British birth, between the ages of twelve and nineteen years, to learn how to use a rifle. The Competition was initially sponsored and supported by Lt. Col. Raymond Ffennell of the South African Defence Force, and it was from his generous gifts and endowments that prizes were provided annually and the administrative expenses of the competition defrayed. All school and college cadet corps throughout the British Empire participated. The competition was described in London papers as the largest sporting event to be taking place in the World at the time. In 1925, 23,000 competitors took part, and in 1938 the number rose to 28,000 in 1,302 competing teams. 

The Lawrence Royal Military School, Sanawar won the coveted Shield for two consecutive years in 1925 and 1926 with the highest individual scores and, in doing so, demolished an Empire record long held by the Australian and New Zealand Schools Cadet Corps. In both years the Chief Instructor, WOI (RSM) G.E. Foster I.U.L was awarded a Bronze medal as Instructor of the best team and a silver medal as premier instructor Junior Division in the Empire. G. E. (George) Foster was himself an Old Sanawarian, (1899-1904). The School was honoured with personal congratulations from H. E. The Viceroy, the Right Honourable, Secretary of State for India, and H.E. The Commander-in-Chief, (India). (See extract from LRMS Orders of 14th April 1926, appended below). 

In recognition of this achievement, a full-size bronze replica of the shield was presented to the School in May 1927 by the National Rifle Association, (inset). For many years thereafter, it served as the official School trophy for inter-House Shooting Competitions and remains to this day on display in the School Museum. 

In 1938 Sanawar won the Imperial Challenge Shield for a third time with an average score of 98.332, taking third place among the best hundred units in the Empire. In addition to winning the Shield, there were several silver and bronze medals awarded to individuals in all eight of the School teams. Norman Kells, the Headboy (1938), achieved the highest possible score of 100. Moreover, he was awarded silver medal as the highest individual scorer in the Empire for three successive years. The School was again honoured with personal congratulations from the Founder of the Imperial Challenge Shields Competitions, Hon. Colonel R.W. Ffennell of the South African Defence Force. (See extract from LRMS Orders of 12th April, 1938, also appended below).

Competition for the Shield ceased during the war years and resumed in 1948 under the name Commonwealth Challenge (Rifle) Shield. An Australian School Cadet team were the first to win the trophy under its new name.