I'm sorry if this isn't the right subreddit to post this question in, but I figured I'd start here. So for some background, I'm Jewish myself and an atheist and I would like to know more about my people's history. The thing is in the search for a source most (if not all) of the books that google or amazon dig up use the Torah as a historical reference, which it definitely is not. If you have a title that has any information on what our religion was (or may have been) before the Babylonian conquest, I'd consider that a plus!
How much do you feel like reading? Although it's a few decades old at this point, Salo Wittmayer Baron's 18-volume series A Social and Religious History of the Jews is still by far the most extensive history of the Jewish people ever published, covering ancient times through the late middle ages and into the era of European expansion. The early history (which is what it sounds like you're interested in) is covered in the first couple of volumes. A bit more recent is the Cambridge History of Judaism, coming in at eight volumes total (I believe Volume 5, which is the final one to be published, is supposed to come out this year or next). If you want a single volume, I think it's hard to do better than A History of the Jewish People, edited by Haim Hillel Ben-Sasson, or Jewish People, Jewish Thought by Robert Seltzer.
Richard Friedman wrote an interesting book called “Who wrote the Bible?” in the late 80’s I really liked. It’s purely academic and outlines the Documentary Hypothesis thinking of the time. It’s short(ish) and attributes authorship to it’s various chapters or even sometimes verses. I’m almost positive his info is dated at this point to some extent as the Dead Sea Scrolls continue to expand our understanding of that time period (if someone wants to suggest an updated source that’d be nifty), but from what I remember it was great for getting your toes wet in ancient Jewish life.