It's interesting how history is always changing. You wouldn't think it would either. After all, what happened, happened. There is no changing an event after it has occurred. However, what we know of events changes frequently.
In a previous post I had mentioned Schliemann excavating at Mycenae. He also found and excavated Troy in Turkey. He was obsessed with this idea that Homer's tales weren't just myths and that they were based in fact. Other scientists at the the time, in fact most all of them, ridiculed him. Schliemann did not have the proper scientific training, they said. If anyone knew anything, these scientists decided, it would be them. Meanwhile, Schliemann just got the permission from the Turks and started digging. It took a long time to convince the scientific community, but he did. Minds were blown. Amazingly enough, he was also one of the first to start actually recording his excavations.
See, when you are on a dig, you are removing information from the ground. The process is irreparably destructive. Once done, there's no putting it back the way it was. This is why note-taking and measuring and map-making is so important. It helps you reassemble the big picture. Sure that gold necklace is super cool, and hey so is that pretty statue. Without taking notes you may never realize that the necklace had at one time been on the statue. So it's pretty amazing that someone outside of the so-called brilliant scientific community recognized this, even if he dug through the Bronze Age Homeric Troy.
No, this is not a Schliemann bio either. I've just been studying early Greek and Minoan history all semester and am reading more about it now, especially on Mycenae. He's just a good example.

http://en.wikipedia.org/wiki/File:Map_of_fertile_cresent.svg
Cyprus is the island to the left

Now, something about history (technically pre-history since it's before written language) that particularly fascinates me is the advent of farming. Bone analysis has shown that people at the start of farming were not as healthy as their foraging counterparts. Low yields, a limited food base, intensive labor, and throw in a bad harvest or two and you've got a situation that quickly leads to malnutrition. It amazes me that people did it anyway. Granted, it was probably gradual, and possibly even accidental at first. But when we first become farmers, boy was it rough. And it spread so quickly. It started in the Levant about 9500 BCE, and spread. According to the latest research (click here for article on the research, it hit Cyprus only a couple hundred years after that. Archaeologically speaking, that's fast. Homo sapiens sapiens had been foraging for thousands of years, and our ancestors for hundreds of thousands (and millions) of years before that. So, thousands to a few hundred is a major change. This is why the introduction of farming is termed the Neolithic Revolution.
Our understanding of the Neolithic Revolution keeps pushing dates further back in history. Once cereals were domesticated, animals soon followed. The major exception to this is that the dog was domesticated beforehand, but that's a different matter entirely. This completely changed how we were living, and directly led to where we are now. It's such an exciting time in humanity's past, and the field is always revealing new information, new understandings of how we became us. Put simply, it's just so freakin' cool.