 Sir Herbert Hope Risley KCIE CSI (4 January 1851 – 30 September 1911) was a British ethnographer and colonial administrator, a member of the Indian Civil Service who conducted extensive studies on the tribes and castes of the Bengal Presidency. He is notable for the formal application of the caste system to the entire Hindu population of British India in the 1901 census, of which he was in charge. As an exponent of race science, he used the ratio of the width of a nose to its height to divide Indians into Aryan and Dravidian races, as well as seven castes.
