[1] There was great disquiet amongst the British, who disliked the idea of serving under native officers; others felt that without good breeding, a public school education, and sufficient suitable training, Indians would not become good officers and would neither be able to lead nor be accepted by the native troops.
Indian proposals for faster induction were rejected, and equally unrealistic plans for Indianisation over forty years, with restricted kinds of commission, were suggested.
During World War II, they fought in the Western Sector against German and Italian forces and in East and Southeast Asia against the Imperial Army of Japan.
Other KCIOs, as battalion commanders or Acting Brigadiers, took Japanese surrender in Andaman and Nicobar, Vietnam, Indonesia, and Philippines.
After World War II, they formed an essential component of the Commonwealth Occupation Forces in Japan.
Cariappa, Rajendrasinhji, and Ayub Khan became C-in-C; Shrinagesh, Thimayya, Chaudhuri, and Kumaramanglam became Chiefs of the army staff.
The eight units selected were:[3][4] The first batch of KCIOs included: Commander-in-Chief Tripura Forces Col. Rana Jodha Jung Bahadur Rana, Amar Singh, Maj. Gen. Ajit Rudra, K.A.D Naoroji (grandson of Dadabhai Naoroji), Field Marshal K.M.
Kaul, Maj. Gen. Ishfakul Majid, Maj. Gen. Ajit Singh Guraya, and Field Marshal Ayub Khan were a few of the Sandhurst-trained officers.
Maj. Gen. Harkirat Singh was twice elected President of the Institution of Engineers (India), was the founding chairman of Bharat Earth Movers Ltd., Chairman of Central Road Research Institute, served as Advisor (Construction) in the Planning Commission, Vice-chairman of Heavy Engineering Corporation, and was the first chairman of the monumental National Building Code of India for which he was awarded the K S Moudgill Prize by the Indian Standards Institution (ISI).
In his honor, the Institution of Engineers (India) holds an annual memorial lecture on his birthday at the Delhi State Centre.