Action Comics is an American comic book series that introduced Superman, the first major superhero character as the term is popularly defined. The publisher was originally known as Detective Comics, Inc., and later as National Comics and as National Periodical Publications, before taking on its current name of DC Comics.

Jerry Siegel and Joe Shuster saw their creation, Superman (also known as Kal-El, originally Kal-L), launched in Action Comics #1 on April 18, 1938 (cover dated June), an event which began the Golden Age of Comic Books. Siegel and Shuster had tried for years to find a publisher for their Superman character (originally conceived as a newspaper strip) without success. Superman was originally a bald madman created by Siegel and Shuster who used his telepathic abilities to wreak havoc on mankind. He appeared in Siegel and Shuster's book Science Fiction. Siegel then commented, "What if this Superman was a force for good instead of evil?" The writer and artist had worked on several features for National Allied Publications' other titles (Slam Bradley in Detective Comics, for example) and were asked to contribute a feature for National's newest publication. They submitted Superman for consideration and, after re-pasting the sample newspaper strips they had prepared into comic book page format, National decided to make Superman the cover feature of their new magazine. After seeing the published first issue, publisher Harry Donenfeld dismissed the featured strip as ridiculous and ordered it never to be on the cover of the series again. However, subsequent reports of the first issue's strong sales and follow up investigations revealed that Superman was the reason, thus the character returned to the covers, becoming a permanent presence in issue 19 onward.