Over the past 110 years, 366 girls and 369 084 boys have been named Louis. The name Louis ranks 5487th in the United States among the most common names for girls. For the first time more than ten times newborns were named Louis in 1910. The peak of popularity of the name Louis came in the 1920s and 1940s. You can see absolute numbers and relative numbers on the chart. Indicators per 100K more accurately assess the popularity of the name.