When “The Simpsons” premiered in 1989, it was an outlier. Animated shows in primetime were by no means unprecedented — “The Flintstones” broke that barrier in the ’60s — but never before had an animated series aimed at adults resonated so powerfully or had as significant an impact on a network as “The Simpsons” did…

via From ‘The Simpsons’ to ‘Solar Opposites,’ Inside TV’s Adult Animation Boom — Variety