I found The Histories by Herodotus [0] to be an amazing read. While it's not 100% accurate as we know today, the time and effort spent compiling this when it was written is definitely impressive. This one is a reasonably lengthy read, but I thoroughly enjoyed it.
Additionally, though it is somewhat biased in favour of the author, The Conquest of Gaul by Julius Caesar [1] was a great look into the campaigns throughout Gaul. And a relatively short read when compared to The Histories.