The Baby Boom generation created a huge market for kid related material in the late 50s and early 60s. There were plenty of cartoons, both old and new, on TV. Most of the Saturday morning cartoons shown on network TV came from California.
Greater New York was home not only to newspaper cartoonists and comic book artists, but animators. Quite a few of the syndicated cartoons that kids watched after school were produced in New York.
Joe Oriolo, a former Fleischer/Famous Studios animator, was behind several popular syndicated TV cartoon series. Looking at these examples now, I admire the industry veterans of theatrical cartoons who succeeded within the limitations of TV animation.
Felix the Cat
The Mighty Hercules
Casper the Friendly Ghost