Who is pictured on the first cartoon character stamp issued by the United States Post Office?

According to Fremont Tribune, Bugs Bunny was the first cartoon character to appear on a postage stamp. The Smithsonian, which operates the National Postal Museum, notes that the stamp was issued on May 22,1997.

By 2014, the Bugs Bunny stamp ranked seventh on the list of top 10 most popular U.S. stamps. The Smithsonian lists Terrence W. McCaffrey as the art director for the stamp, and more than 40 different designs were created. The decision to put a cartoon character on a stamp was unexpectedly controversial. Stamp collectors feared that it would make the commemorative stamp program too commercialized, while others were afraid that stamps would start to feature more cartoon characters and fewer historical figures.