Dyarchy was introduced as a constitutional reform by Edwin Samuel Montagu (secretary of state for India, 1917− 22) and Lord Chelmsford (Viceroy of India, 1916 − 21). It marked the first introduction of the democratic principle into the executive branch of the British administration of India. Though much criticized, it signified a breakthrough in British Indian government and was the forerunner of India's full provincial autonomy (1935) and independence (1947).