Afterward, the Duke and Duchess of Cambridge hosted a tea party at Clarence House and served a portion of their wedding cake that they had saved since 2011.
Louis' godparents are a mix of close friends and family members: Nicholas van Cutsem, Guy Pelly, Harry Aubrey-Fletcher, The Lady Laura Meade and Robert Carter are all friends of the Duke and Duchess' and and Lucy Middleton is Kate's cousin.
Prince Louis was christened at The Chapel Royal at Saint James's Palace in London, England, on Monday.
Princess Charlotte stole the show today as she saluted RAF pilots as they flew across the skies above Buckingham Palace.
Royal fanatics, who had been camped outside the hospital wing for several days in anticipation, jumped for joy and popped open champagne as the news of his birth was announced.
Princess Charlotte had a sassy message for photographers as she left her brother's christening on Monday: "You're not coming". Prince William was by Kate's side, supportive as ever. At affair, the 34-year-old socialite donned a gorgeous baby blue dress to her nephew's outing that cut a similar style to the Alexander McQueen number her 36-year-old royal sis wore to her 2017 wedding.
Prince Louis now sits at fifth in line to take the throne after his grandfather Prince Charles, father Prince William, big brother Prince George and big sister Princess Charlotte.
Princess Charlotte wore a blue smock dress and matching bow headband.