Harassing and hateful speech in online spaces has become a common problem for platform maintainers and their users. The toxicity created by such content can discourage user participation and engagement. Therefore, it is crucial for and a common goal of platform managers to diminish hateful and harmful content. Over the last year, Reddit, a major online platform, enacted a policy of banning sub-communities (subreddits) that they deem harassing, with the goal of diminishing such activities. We studied the effects of banning the largest hateful subreddit (r/fatpeoplehate or FPH) on the users and other subreddits that were associated with it. We found that, while a number of outcomes were possible --- in this case the subreddit ban led to a sustained reduced interaction of its members (FPH users) with the Reddit platform. We also found that the many counter-actions taken by FPH users were short-lived and promptly neutralized by both Reddit administrators and the admins of individual subreddits. Our findings show that forum-banning can be an effective means by which to diminish objectionable content. Moreover, our detailed analysis of the post-banning behavior of FPH users highlights a number of the behavioral patterns that banning can create.