A statement was released on the royal couple’s official Instagram account, revealing that the baby was born before 6am and weighs 7lbs. 3oz.
The first pictures of the couple with their newborn were revealed on Wednesday. The newborn was seen swaddled in a white blanket wearing a white hat.
The couple later announced on Instagram that they had named their son Archie Harrison Mountbatten-Windsor.
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Welcome to The Independent's royal baby live blog, giving you all the latest news on the upcoming arrival of the Duke and Duchess of Sussex's first child.
Having told well-wishers in January that she was six months' pregnant, many believe that the duchess will give birth to the royal baby any day.
If the royal baby is a girl, then she may receive a special heirloom from her mother, the Duchess of Sussex.
During an interview with Hello! magazine in 2015, the duchess, then an actor on legal television drama Suits, revealed that she bought herself a Cartier French Tank watch when she was informed that the show had been renewed for a third season.
The duchess had the watch engraved with the message: "To M.M From M.M," and said she plans to "give it to my daughter one day".
↵When the royal baby is born, they won't receive a royal title, unless they're granted one by the Queen.
The baby will be known as a Lord or Lady, rather than HRH or a Prince or Princess, like their cousins Prince George, Princess Charlotte and Prince Louis.
However, this could change, should the monarch decide to issue a new Letters Patent, as she did for the Duke and Duchess of Cambridge's children seven years ago.
In 2012, the Queen issued a Letters Patent declaring that "all the children of the eldest son of the Prince of Wales should have and enjoy the style, title and attribute of royal highness with the titular dignity of Prince or Princess prefixed to their Christian names or with such other titles of honour".
With the royal baby due to arrive any day, many are wondering whether the Duke and Duchess of Sussex will decide to depart from or stick to tradition when naming their first child.
The most popular name for male members of the royal family is Albert, with 12 royal babies granted the name since Queen Victoria's birth in 1819.
The most common name among female royal babies is Victoria, a moniker given to nine royal babies over the past two centuries.
So will Prince Harry and Meghan go down the more traditional route? Only time will tell.
There's nothing the British public loves more than betting on possible names for an upcoming royal baby.
According to Oddschecker, a website that compares the odds from multiple betting sources, the majority of people seem to think the baby will be a girl, with eight out of the 10 most popular names among betters being traditionally female.
The name Diana has 12-1 odds, after Prince Harry's late mother, Diana, Princess of Wales.
Meanwhile, the second name on the list is Victoria, the name of Prince Harry's great-great-great-grandmother Queen Victoria, and the second is Alice, taking after the duke's great-grandmother, Princess Alice of Battenberg.
The names Arthur and James both carry odds of 16-1.
One of the most common questions surrounding the birth of the royal baby has been concerning whether or not the child will have dual citizenship.
While it hasn't been confirmed what citizenship the baby will be born with, current laws dictate that the Duke and Duchess of Sussex will be able to apply for dual citizenship for their child.
As the child of Prince Harry, the baby will automatically become a British citizen.
As the duchess was born and grew up in Los Angeles, California, the baby may also be granted a US citizenship, in accordance with the laws outlined by the US Department of State.
There's no doubt that the Duke of Sussex will have his work cut out for him as a new father when the royal baby arrives.
But is the royal likely to take a step back from his official duties, in order to make the most of paternity leave?
Should Prince Harry decide to take some time off after the birth of his first child, he wouldn't be the first royal to do so.
His brother, the Duke of Cambridge, took two weeks' paternity leave after the births of Prince George in 2013 and Princess Charlotte in 2015.
However, following the birth of Prince Louis in 2018, the duke returned to work just two days later.
Earlier this month, the Duke and Duchess of Sussex asked well-wishers to donate to several charitable organisations, rather than send them gifts in celebration of the upcoming birth of the royal baby.
"Their Royal Highnesses wanted you to know the impact of your support – the direct effect your donation, energy, and action made! YOU chose to be part of the collective good, and you have made a real difference," the caption read.
Some are under the impression that the first name given to the royal baby must be approved by the Queen.
However, while it's the Queen's decision whether or not the child will be granted a royal title, the decision over the baby's name is believed to be a more informal discussion.
The arrival of a royal baby requires the strict following of many customs, including a formal statement presented on an easel outside Buckingham Palace and the announcement of the name a few days after the birth.
The Queen is always the first person to be informed of a royal birth, before the news is made more widely known to the general public.
Here's a step-by-step guide of what happens when a royal baby is born.
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