What have been the most egregious examples of dishonesty or retrospectively incorrect positions entering the scholarly consensus in the history of academia?

by Vortigern
TheVegetaMonologues

You're probably not gonna get any responses here. There's a rule against "throughout history" questions

Reedstilt

I removed this not only for the issue of "throughout history" questions, but because it's a poll-type question.

During our Friday Free-for-All, when the rules are little looser, you can ask there if you feel like taking a second shot at this.