Colonel Maharaja Sri Sir Krishna Raja Wadiyar IV, GCSI, GBE, (June 4, 1884-August 3, 1940, Bangalore Palace) also known popularly as Nalvadi Krishna Raja Wadiyar was one of the most celebrated rulers among the Indian States when India was still under British rule. At the time of his death, he was also one of the world's wealthiest men, with a personal fortune estimated in 1940 to be $400,000,000 which would be the equivalent of a billion today.

He was a philosopher-king, who was seen by Paul Brunton as living the ideal expressed in Plato’s Republic. He had been compared to the Emperor Ashoka by the English statesman Lord Samuel. Mahatma Gandhi called him Rajarshi, or "saintly king", and his kingdom was described by his followers as Rama Rajya - an ideal kingdom akin to the mythological rule of Lord Rama.

Krishna IV was the 24th ruler of the Wodeyar dynasty of Mysore that ruled over Mysore State from 1399 to 1950. He was the eldest son of Maharaja Chamaraja Wadiyar IX and Maharani Vani Vilas Sannidhana. He was born on June 4, 1884, at the Royal Palace, Mysore. After the death of his father in Calcutta in 1894, Krishna's mother ruled the state as Regent until Krishna reached the age of majority.