We really can not know this. We can only infer from cultures and religions in the relatively short timespan covered by written history. And even then, morality has changed significantly through time. A simple example - would you think that someone telling a story about someone else beating his wife to a pulp is something to laugh about?

Here, check out how the audience reacts just a bit more than 50 years ago: https://www.youtube.com/watch?v=ccyu44rsaZo

I think the only moral that may have been something close to universal throughout times would've been something like: "Don't kill a member of in-group without a good reason if you're not the head honcho."

Everything else? We have literally no idea.

EDIT: Really, watch the video, it actually applies to the discussion really well. It's basically an argument about morals.

I think outright religious bans on murdering, raping or enslaving people outside of your community are fairly recent developments. Even the old testament is fairly ambiguous on this.