Kate and William's decision to call their newborn son Louis has sent social media into a frenzy with many fascinated they chose a name most popular in France.
The fifth in line to the British throne shares the same moniker as 18 kings from across the Channel and many reacted with a 'sacre bleu' when they heard the news according to DailyMail.
BREAKING: In a defiant two fingers to Brexit, William & Kate have given their baby a French name: Louis. One used by 18 French kings. pic.twitter.com/HWHQ1paJNP
Piers Morgan suggested in a tongue-in-cheek tweet: "In a defiant two fingers to Brexit, William & Kate have given their baby a French name: Louis. One used by 18 French kings".
Twitter offered its typical kaleidoscope of views but many focused on the Gallic roots of the name Louis, which means "renowned warrior", and linked it to Britain's ongoing divorce from the EU.
Reactions included: "That means Will and Kate are Remainers", "I guess after Brexit it will become Lewis" and "So the royal baby has a French name.. sacre bleu!"
And a vocal minority have hailed it as a great choice because it is the name of the orangutan from Disney favourite The Jungle Book or jokingly suggested Kate and William love One Direction's Louis Tomlinson and the X-Factor's Louis Walsh.
Tomlinson tweeted about the name and said: "Young Louis welcome to the world. I'll take you under my wing lad. The Adidas tracksuit is in the post!".
Pottermore, author JK Rowling's publishing company, has pointed out that Louis, Arthur and Charles are all members of the famous Weasley family from the Harry Potter books.
The official Twitter account tweeted: "Louis Arthur Charles, you were named after three iconic Weasleys... #RoyalBabyName"
The name, also one of Prince George's middle names, is French and German in origin. Louis is pronounced Lou-ee, rather than Lew-is - but some joked it would change to the latter Anglicised version post-Brexit.
Louis was the 71st most popular name in England and Wales, according to the latest available figures from the Office for National Statistics.
In 2016, just 911 boys were given the name Louis in England and Wales.
Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge depart the Lindo Wing with their newborn son Prince Louis of Cambridge at St Mary's Hospital. Photo / Getty
It was more popular in the early 2000s when it ranked around 39th, but was not popular throughout the 20th century.
Louis has been the name of many rulers across the world, including 18 kings of France.
The first was Louis I, known as "Louis the Pious", who reigned between 778 and 840.
The most famous was Louis XIV, known as the Sun King, whose reign started aged 4 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.
