One obvious link is with Prince Louis' grandfather, Prince Charles, while the name may also be a tribute to Louis Mountbatten.
Mountbatten was Duke of Edinburgh Prince Philip's uncle and mentor. He encouraged his nephew to marry Queen Elizabeth, and was considered an "honorary grandfather" by Prince Charles, according to the MailOnline. Mountbatten was killed by an IRA bomb in 1979.
Louis is also the middle name of both Prince William and his eldest son Prince George. Their full names are William Arthur Philip Louis and George Alexander Louis respectively.
Bookies' favourites for the new royal's name had included Alexander, Arthur, James, Philip, and Albert. Louis was 20/1 with some, meaning people could have made a healthy profit if they had bet on the name.
Louis is currently the 71st most popular name for a baby boy in England and Wales, according to Press Association journalist Ian Jones. It could well climb in the rankings in the same way Charlotte did after Princess Charlotte was named.
Louis is currently the 71st most popular name for a baby boy in England & Wales, ranking behind the likes of Teddy, Harvey, Hugo and Reggie.— Ian Jones (@ian_a_jones) April 27, 2018
Kensington Palace announced the new Prince's name in a tweet on Friday. "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," it said.