DC Comics fans have been all about Justice League on Thursday, mainly because it marks exactly one year until the Justice League movie is released in theaters. One thing that many have forgotten, however, is that Justice League has premiered on November 17 once before.

On this date, in 2001, the Justice League animated series debuted on Cartoon Network.

The series was a groundbreaking effort from Warner Bros Animation, and it lead to many more films and TV series. Fan favorites like Young Justice, Teen Titans, and the Justice League films would not have been possible without this series coming first. To give credit where credit is due, Justice League wasn't the first outright hit from the studio. Batman: The Animated Series aired in the early 90s and had a heavy influence on both animation and comics going forward.

Kevin Conroy, who voice Batman for Justice League and Batman: The Animated Series, tweeted a message to fans on Thursday morning. In his post, he mentioned that the original series had aired 15 years ago on this date, and that he had only fond memories of his time on the project.

15 years ago Justice League premiered. Great cast, loved working with them, became good friends pic.twitter.com/1nLlmbV8Hw — Kevin Conroy (@RealKevinConroy) November 17, 2016

When you think about the logisitics, it had to have been difficult to get those dates to line-up. The fact that the original premiere date for the animated series happened to land on a Friday around the time the Justice League film would be ready to hit theaters makes this a very touching connection to fans.

If you're looking forward to Justice League, as you very well should be, maybe spend the next year watching back through the animated series. It has been regarded as one of the best the studio has ever done, and it will only make you more excited for the upcoming film.

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