The Sumi Naga is one of the major Naga tribes in Nagaland, India. The Sumis mainly inhabit the Zunheboto district, although many have migrated outside Nagaland for work and education. They are also the most united and aggressive tribe. Since times immemorial, the other tribes of Nagas have feared the Sumi tribe. Despite their ferocity and aggressive nature in warfare, the Sumi Tribe is also known for their simplicity and honesty. Their loyalty towards their tribesmen and friends is unparalleled. The Sumis practised headhunting like other Naga tribes before the arrival of the Christian missionaries and their subsequent conversion to Christianity. Anthropological study of the Sumi tribe is documented in the book The Sema Nagas by J. H. Hutton, who was a Professor of Social Anthropology in the University of Cambridge. The Sumi is one of the recognised scheduled tribes of India.