As a journalist, Henry Louis (H. L.) Mencken had little work during World War I because of his pro-German sympathies. To stay busy, he explored a subject that fascinated him: the evolution of American English from British English. The result, The American Language, was published in 1919. Mencken began working on the book in 1910, while still working for the Baltimore Sun. After the book's publication, Mencken received additional material from people all over the country. As a result, revised editions of the book were published in 1922, 1923, and 1936, and supplements were released in 1945 and 1948. These additions included more examples and explanations of regional expressions, dialects, and other speech developments and characteristics. Mencken's interest in identifying uniquely American cultural features is evident in his work in The American Language. He sought to discover traditions native to the United States, and his exploration of American English turned up many such traditions.

To Mencken's—and his publisher's—surprise, the lengthy volume was an immediate bestseller. With an initial release of only fifteen hundred copies, the book sold out rapidly. Its popularity is attributed to the logical, easy-to-follow presentation of research and theories couched in Mencken's characteristically witty, spirited prose. Today, it is read mainly by students, as it has retained its value as a seminal work in American linguistic study.