George Tupou V (Tongan: Siaosi Tupou V, full name: Siaosi Tāufaʻāhau Manumataongo Tukuʻaho Tupou V; 4 May 1948 – 18 March 2012) was the King of Tonga following the death of his father, Tāufaʻāhau Tupou IV in 2006, until his own death six years later.

Tupou V was born on 4 May 1948. He was the eldest son of King Tāufaʻāhau Tupou IV (1918–2006) and Queen Halaevalu Mataʻaho ʻAhomeʻe (born 1926). He was appointed Crown Prince on 4 May 1966. In that role, he was better known by one of his traditional chiefly titles, Tupoutoʻa.

Tupou V attended King's School and King's College, both in Auckland. This was followed by periods at The Leys School in Cambridge, and another school in Switzerland. He also studied at Oxford University and the Royal Military Academy Sandhurst in England.

Though unmarried, Tupou V had a daughter born out of wedlock, 'Ilima Lei Fifita Tohi (born 1974). She married police officer Tulutulumafua i'Olotele Kalaniuvalu in 1997, and has three children. According to the Constitution of Tonga, ʻIlima is ineligible to accede to the throne as only children born of a royal marriage may inherit the royal succession.

George V (George Frederick Ernest Albert; 3 June 1865 – 20 January 1936) was King of the United Kingdom and the British Dominions, and Emperor of India, from 6 May 1910 through the First World War (1914–1918) until his death in 1936.

George was a grandson of Queen Victoria and Prince Albert and the first cousin of Tsar Nicholas II of Russia and Kaiser Wilhelm II of Germany. From 1877 to 1891, he served in the Royal Navy. On the death of Victoria in 1901, George's father became King Edward VII, and George was made Prince of Wales. On his father's death in 1910, he succeeded as King-Emperor of the British Empire. He was the only Emperor of India to be present at his own Delhi Durbar.

As a result of the First World War, other empires in Europe fell while his expanded to its greatest extent. In 1917, he became the first monarch of the House of Windsor, which he renamed from the House of Saxe-Coburg and Gotha as a result of anti-German public sentiment. His reign saw the rise of socialism, communism, fascism, Irish republicanism, and the Indian independence movement, all of which radically changed the political landscape. The Parliament Act 1911 established the supremacy of the elected House of Commons of the United Kingdom over the unelected House of Lords. In 1924 he appointed the first Labour ministry and in 1931 the Statute of Westminster recognised the dominions of the Empire as separate, independent kingdoms within the Commonwealth of Nations. He was plagued by illness throughout much of his later reign and at his death was succeeded by his eldest son, Edward VIII.