In case you have such an issue, and verify that you don’t call history.push() 2 times, check your content for an iframe.
TL; DR: React tries to minimize re-rendering and will reuse the iframe element by just changing its src. This will update the history object, which is apparently shared with the main page (and would need to press the back button multiple times).
The solution is to add a unique key to the iframe (I used the src URL itself)
Here is a blog post that explains the issue in-depth:
https://www.aleksandrhovhannisyan.com/blog/react-iframes-back-navigation-bug/