This name experienced a rise in popularity at the end of the 20th century. It was the most popular name for girls in England and Wales from 2011 to 2015.
Apart from royalty, this name was only moderately popular in France during the Middle Ages. After the French Revolution, when Louis XVI was guillotined, it became less common.
The Normans brought the name to England, where it was usually spelled Lewis, though the spelling Louis has been more common in America. Famous bearers include French scientist Louis Pasteur (1822-1895), French actor Louis de Funès (1914-1983), Scottish author Robert Louis Stevenson (1850-1894), who wrote Treasure Island and Dr Jekyll and Mr Hyde, and American jazz musician Louis Armstrong (1901-1971).
As an English name, it has been used occasionally since the 12th century. It is the name of a central character in Shakespeare's play The Two Gentlemen of Verona (1594).