Prince William and Kate Middleton announced their baby son would be called George Alexander Louis.
William and Kate’s baby will be known as Prince George and is third in line to the British throne.
Kensington Palace said in a short statement: “The Duke and Duchess of Cambridge are delighted to announce that they have named their son George Alexander Louis.
“The baby will be known as His Royal Highness Prince George of Cambridge.”
Six King Georges have worn the crown throughout history since the German-born George I, the first Hanoverian king of Great Britain, acceded to the throne in 1714.
The last was the Queen’s father George VI who died in 1952 but was known to his family as Bertie.
George was the most popular name with the bookies with betting firms William Hill, Coral and Paddy Power all offering short odds on the moniker.
The name Louis is likely to be a tribute to Lord Louis Mountbatten, the Duke of Edinburgh's uncle and the last British Viceroy of India before independence in 1947.
He was known by the Royal Family as Uncle Dickie, and was assassinated by the IRA in August 1979.
His boat was blown up on a fishing trip off the coast of County Sligo, Republic of Ireland.