The Warner siblings are based in a roundabout way on senior producer Tom Ruegger's three real-life children. Originally, they were going to be ducks named Yakki, Smakki and Wakki, but this idea was canned (it was thought to be too similar to DuckTales), and the three were changed into platypi, then into Bosko-like inkblots. Along the way, they gained a female friend; finally, Yakki became Yakko, Smakki and Wakki were combined into Wakko, and the female friend was named Dot and made their sister.
One of the regulars (Ralph the Guard) was a recurring character in the later episodes of Tiny Toon Adventures; also, several other characters have made cameo appearances, and the theme song from it shows up occasionally as well. See also Pinky, Elmyra & the Brain.
Kathryn Page, who is credited with all sorts of crazy things (see the Crazy Credits section), is really one of the assistants of the show's senior producer, Tom Ruegger.
The Pinky and the Brain sketch titled, "Yes, Always", was taken virtually word for word from a recording of Orson Welles doing a commercial and berating the director and his suggestions for Welles' delivery. In this recording, Welles uses some rather bad language, which was changed for the sketch.
After a few seasons the line "Bill Clinton plays the sax" was removed from the opening credits. It was briefly replaced with the line "We have wisecracks by the stacks", but it soon gave way to "We pay tons of income tax". In some cases "We have baloney in our slacks" was also used.
Nathan Ruegger's voice began to change while voicing Skippy Squirrel. Rather than recast the part, the studio began altering his voice recordings to make them sound higher.
When Tom Ruegger created Buster Bunny for Tiny Toon Adventures he wanted to create a catch phrase (to parallel Bugs' "What's up, Doc?"). All he could think of was the old vaudeville standby "Hello, nurse!" but that made no sense for the character. Now the phrase is used by Yakko and Wakko when greeting Dr. Scratchansniff's attractive assistant.
The CEO, Thaddeus Plotz's last name is Yiddish for "explode."
The water tower where the Warners live and many other features of the Warner lot are rather accurate representations of the Warner Studios lot in Burbank California. (Although, the real water tower is all gold, not red on top.)
During the theme song the characters proudly anounce that "We have pay or play contracts". This is a Hollywood term meaning the performer is paid whether or not he plays - this was a big deal in the days of contract studio players.
The Animaniacs theme is in part a satire of "This Is It", the theme song from The Bugs Bunny Show. For example, Bugs and company sing "No more nursing, rehearsing a part. We know every part by heart." The Animaniacs sing, "The writer's flipped. We have no script. Why bother to rehearse?"
In the opening of the Pinky and The Brain segments, Brain writes "THX=1138" on the blackboard. This is a reference to THX 1138, written and directed by George Lucas. Lucas is good friends with Steven Spielberg, Executive Producer for Animaniacs.
The Goodfeathers theme song is a parody of 'That's Amore' by 'Dean Martin'.
The shape of Dot's head mimics the shape of the Warner Bros. shield logo.
The Goodfeathers, a satire of the Warner Brothers film Goodfellas were made to reflect the personalities of the film's main stars. Bobby the blue pigeon is meant to be Robert De Niro, Pesto the purple pigeon is meant to be Joe Pesci, and Squit the gray pigeon is meant to be Ray Liotta.
Whenever someone says something that could be interpreted as being a dirty joke, Yakko blows a kiss to the audience, and says, "Goodnight everybody."
Writer/producer Sherri Stoner created Slappy the Squirrel after her friend and fellow writer John P. McCann made fun of her career playing troubled teenagers. McCann said she'll be playing troubled teens into her fifties. So she went the other direction, and created an older person acting like a teenager.
Jess Harnell normally provided the voice for Wakko. However, for the Great Wakkorotti belching segments, the voice is provided by Maurice LaMarche.
Jess Harnell said that he did a John Lennon impression when he went to audition for the role of Wakko, and it went great.
Executive Producer Steven Spielberg came up with the idea to have an original musical score in every episode.
The music for the series was provided by a 35 piece orchestra and scored by a team of six composers.
Steven Spielberg said that the humor of social commentary and irreverence of the Warners were inspired by the Marx Brothers and the Looney Tunes cartoons.
The Wheel of Morality segments were created to fill time when an episode was running short.
The character of Minerva Mink was scaled back because the network censors deemed her too sexually suggestive for the show's intended audience.
After all of the characters were created, they were shown to Executive Producer Steven Spielberg for final approval. Buttons and Mindy were chosen by his daughter.