Who created the American comic strip, 'Dennis the Menace'?

'Dennis the Menace' is a daily syndicated newspaper comic strip originally created, written, and illustrated by Hank Ketcham. It debuted on March 12, 1951, in 16 newspapers and was originally distributed by Post-Hall Syndicate. It is now written and drawn by Ketcham's former assistants, Marcus Hamilton (weekdays, since 1995), Ron Ferdinand (Sundays, since 1981), and son Scott Ketcham (since 2010), and distributed to at least 1,000 newspapers in 48 countries and in 19 languages by King Features Syndicate. The comic strip usually runs for a single panel on weekdays and a full strip on Sundays.

The comic strip became so successful that it was adapted to other popular media, including several television shows, both live-action and animated, and several feature films, including theatrical and direct-to-video releases.

Coincidentally, a UK comic strip of the same name debuted on the same day, though the issue in question bore the cover date of March 17. The two are not related and change their names subtly in each other's respective home bases to avoid confusion.