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).
This name died out after the Middle Ages, but was revived in the 19th century. In America and other countries it became fairly popular in the second half of the 20th century. A famous bearer of the surname is former basketball star Michael Jordan (1963-).
It has only been commonly used as a given name since the 20th century, influenced by two plays featuring the character: William Butler Yeats' Deirdre (1907) and J. M. Synge's Deirdre of the Sorrows (1910).