In a statement the palace said: “The Duke and Duchess of Cambridge are delighted to announce that they have named their son Louis Arthur Charles.

“The baby will be known as His Royal Highness Prince Louis of Cambridge.” 

The prince is the duke and duchess’s third child, the younger brother of Prince George and Princess Charlotte, and the Queen and the Duke of Edinburgh’s sixth great-grandchild.

Lord Louis Mountbatten was Prince Charles’s beloved great-uncle who was assassinated by the IRA in 1979. Prince Louis of Battenberg was the Duke of Edinburgh’s grandfather’s name.

The three names are popular choices recycled by the royal family. Prince Charles is Charles Philip Arthur George, while Prince William is William Arthur Philip Louis. Prince George’s full name is George Alexander Louis.

Bookmakers had Arthur as the favourite for some time, then Alexander.

It has taken four days for the new prince’s name to be released. He is fifth in line to the throne, and was born on Monday weighing 3.8kg (8lbs 7oz).

Both Prince George and Princess Charlotte’s names were released two days after their births. But Prince William’s name was not made public for seven days.

Historically royal names are not usually announced for several days. Prince Harry was a recent exception. It was confirmed on the day he left hospital that he would be called Henry, though would be known as Harry. Prince Charles’s name was revealed one month after he was born, only being declared ahead of his christening in the Music Room at Buckingham Palace in December 1948.

The Queen is told, as a courtesy, before the name is announced.

Bookmakers celebrated the news. Alex Apati of Ladbrokes said that Louis had been placed 10th in terms of bets wagered, with odds as long as 20/1.

“Prince Louis has caught both bookies and punters by surprise. With it being one of Prince George’s middle names fans didn’t see it as an obvious frontrunner for Kate and Wills second son,” he said.

The announcement is likely to spark a revival in popularity of the name. While more common in the early 2000s, it had dropped to 71st place in most popular names in England and Wales according to the latest Office of National Statistics figures.

Blackpool Zoo immediately announced a baby Louis of its own in celebration, bestowing the name on a newborn baby double-humped Bactrian camel calf also born on Monday morning.

More about: #Royal-Family