The Duchess of Cambridge gave birth to her third child with her husband Prince William by her side on April 23.
After four days of feverish speculation, Kate Middleton and Prince William finally revealed their third child's name – Louis Arthur Charles Cambridge – at 11.00am on Friday, April 27.
The name is French and German in origin and means 'renowned warrior'. It is one of William's middle names, and Prince George also has it as a middle name.
Lord Mountbatten was born Prince Louis of Battenburg in Windsor in 1900. His great-grandmother was Queen Victoria and his sister was Princess Alice of Battenberg, Prince Philip's mother.
Arthur is William's middle name and a link to the legendary King Arthur adds a special Royal pedigree. The name means 'Bear' - currently a popular baby name in its own right - and the 'Art' link suits this pair of History of Art graduates perfectly.
Charles is a time-honoured Royal name and ever popular with the upper classes, making it the perfect way to honour William's father. It means 'man' or 'warrior' and suits our new Bonnie Prince. It is considered an unlucky royal name for a king as Charles I was executed and Charles II's reign featured the plague and the Great Fire of London.
Kensington Palace made the announcement at 11am this morning. William and Kate have plumped for a moniker used for centuries across the Channel by the French, who have had 18 kings called Louis.
The first French king Louis I, known as 'Louis the Pious', reigned between 778 and 840.
The most famous was Louis XIV, known as the Sun King, whose reign started aged four and lasted 72 years and 110 days - the longest recorded of any monarch of a sovereign country in European history. Queen Elizabeth's reign is currently in its 66th year.
The last one was Louis XVIII - who reigned for a year until Napoleon took power for a second time in 1815 and ensured the monarchy was destroyed.
The name serves as a touching nod to Lord Mountbatten, great- grandson of Queen Victoria and uncle to Prince Philip.
His full title was Admiral of the Fleet Louis Francis Albert Victor Nicholas Mountbatten, 1st Earl Mountbatten of Burma.
In 1979, Mountbatten, his grandson Nicholas, and two others were killed by the Provisional Irish Republican Army (IRA), which had placed a bomb in his fishing boat, Shadow V, in Mullaghmore, County Sligo, Ireland.