 As the nephew of the young and unmarried King Siaosi Tupou II, Tungi was the Heir-to-the-Throne, until the King's marriage and the birth of his first child, The Princess Sālote, in 1900.In 1911 Prince Tungi represented the Tongan King at the Coronation of King George V in London.Tungī was educated at Tupou College, Tonga and Newington College, Sydney, commencing in 1896, aged nine.