One of the oldest comic strips, and the oldest still in syndication, Katzenjammer Kids debuted in 1897 in the American Humorist, a Sunday supplement of the New York Journal newspaper, along with the slightly older strip The Yellow Kid. It was created by Rudolph Dirks.

It was inspired by Max Und Moritz, famous German children's stories of the 1860s. The Katzenjammer Kids featured Hans and Fritz, twins who rebelled against authority, particularly in the form of their mother, Mama; der Captain, a shipwrecked sailor who acted as a surrogate father; and der Inspector, an official from the school system. Several of the characters spoke in stereotypical German-accented English.

The comic strip was turned into a stage play in 1903, inspired several animated cartoons, and was the subject of a commemorative stamp by the US Postal Service in 1995.

It was so popular that it became two competing comic strips and the subject of a lawsuit. This happened because Dirks wanted to take a break after about 15 years but the Hearst newspaper syndicate wouldn't allow it. Dirks left anyway and the strip was taken over by Harold Knerr. Dirks sued, and after a long legal battle the Herst papers were allowed to continue The Katzenjammer Kids and Dirks was allowed to syndicate an almost identical strip, called The Captain and the Kids, for the rival Pulizer newspapers. Both strips ran in competing newspapers for half a century, and fans still debate which was better.

As of 2003, The Katzenjammer Kids is drawn by Hy Eisman and distributed by King Features.