As we know, history tends to repeat itself. If you’ve ever been a student of the subject, then you know this applies to learning it, too. You have to rehash the same details over and over in order to memorize them. And yet, in all of your time spent poring over books and study materials, you may have left out a few details. It’s not your fault, though, as even the most iconic of historical events seemingly haven’t been told in their entirety. So, brush up on these 40 moments in time to learn how they differ from our memories – or studies – of them.