Edwin Montagu, the Secretary of State for India (1917-1922), was the primary architect of the Montagu-Chelmsford Reforms which introduced Dyarchy in the Government of India Act 1919. While Chelmsford was Viceroy, the concept and policy originated from Montagu's declaration of 1917 promising gradual development of self-governing institutions. Tez Bahadur Sapru and Lionel Curtis were advisors, not the originators.