Karlsson-on-the-Roof (Swedish: Karlsson på taket) is a character who figures in a series of children's books by the Swedish author Astrid Lindgren. A cartoon adaptation of the series became popular in the Soviet Union when it was released in the 1970s.

These adaptations are still celebrated as an integral part of the Russian cartoon industry. Karlsson, together with Cheburashka and other such characters, are recognized as a national icon. Lindgren may have borrowed the idea for the series from a similar story about Mr. O'Malley in the comic strip "Barnaby" (1942) by Crockett Johnson.

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