Depending on where you lived and when you grew up, it’s possible you might have known more than one person with the same name. Maybe there was a Jennifer A. and a Jennifer L., or maybe you knew four different people named Michael. Year after year, decade after decade, there are trends in baby names that draw on history, religion, and cultural references. Here are the most popular baby names in the United States during each decade of the 20th century.
Between 1900 and 1909, the most popular name for boys in the U.S. was John, and the most popular girls’ name, by a long shot, was Mary. This is according to data from the U.S. Social Security Administration, based on people applying for Social Security cards. There were 84,591 applications under the name John, and 161,504 entries for Mary. These two names popped up time and time again throughout the 20th century. Both names come from the Bible — John is one of Jesus’ disciples, and Mary is the name of both Jesus’ mother and Mary Magdalene. After John, the most popular boys’ names of this decade were William, James, George, and Charles, and the most popular girls’ names after Mary were Helen, Margaret, Anna, and Ruth.
Between 1910 and 1919, the most popular names were once again John and Mary. In this decade, there were 376,312 registered Johns and 478,637 Marys. Why the sudden jump? For one, the Social Security Administration began collecting data in 1937, so anyone born before that was only counted if they applied for a Social Security card after 1937. (That means the data for the 1900s, 1910s, and 1920s is based on people who listed their birthdays in these decades despite obtaining cards later in life, and doesn’t count anyone born in this period that didn’t apply for a Social Security card.) The U.S. also saw a population spike as infant mortality rates decreased throughout the 20th century, thanks to advances in health care and better access to clean water.
In the 1910s, for the second decade in a row, the second most popular names for boys and girls were William and Helen, respectively, followed by James, Robert, and Joseph for boys, and Dorothy, Margaret, and Ruth for girls. William has long been a popular English name dating back to William the Conqueror, who became the first Norman king of England in the 11th century. Helen, meanwhile, has its origins in Greek mythology: Helen of Troy was a famous beauty, known as the “face that launched a thousand ships.”