BACKSTORY:

Tom Katz, a prodigious Depression-era Toontown star, started out as a recurring background character in a number of inkblot cartoons.
After a restyle, the new Katz first debuted as a side character in Merrie Melodies films during the mid-thirties... audiences immediately noticing the resemblance to childhood favorite film star Felix the Cat. Advancements in color gradation allowed for the restyled Katz to be aired with his more distinct three colors (black, white, gray) as opposed to previously dichromatic film.

By the late 30s, Tom Katz had become a fan-favorite, however a controversial commerical had pushed him down the ranks...
Having featured in an advertisement for a failing cigar business, Katz's popularity dropped as more middle-class consumers were switching to cigarettes... especially given that most of the demographic base he was advertising to (moderate income urbanite parents) were uninterested in the high prices of cigars, increasingly seen as a luxury item during the Depression. The studio then shunted Katz to supporting roles as the Looney Toons rose in stardom. Katz saw a momentary reprisal in the early fourties as the U.S. government approached animation studios for wartime propaganda deals, Tom Katz appearing in the War Bonds advertisement film "Give those Krauts a Wallop!"

The cat's popularity effectively diminished post-war, with other 50's staples taking the spotlight through the decade.
With the rise in Hanna-Barbera's Saturday Morning cartoons during the 1960s, Tom Katz was given an experimental reprisal cartoon, rebranded as "The Tomcat Show," alongside a tweaked design. It is noteworthy that although most other Toontowners had switched to a Technicolor design, Katz remained black, white, and gray, albeit with higher color definition and contrast.
Receiving mixed reviews, The Tomcat Show was cancelled early, leaving Tom Katz to be more or less forgotten about by mainstream animation studios well into the 70s and early to mid 80s.
It wasn't until his background appearance in the 1988 film "Who Framed Roger Rabbit?" that Katz gained a "cult classic" status, regaining popularity in the late 80s and throughout the 90s as an icon alongside other "retro" characters such as Betty Boop.

The popularity of Katz in the late 90s was comparable to comic strip character Garfield, both with wide audience appeal. Today, Tom Katz remains an audience favorite for merchandise such as t-shirts, mugs, and other collector's items.
He has also appeared in several parody videos and internet memes since another mild resurgence in the mid-2000s.