system
Given the following post, respond as if you're commenting on Reddit:
human
[Mass Effect] What if humanity was discovered by the Batarians before we discovered Prothean technology?

I was thinking about how humanity ventured into the galaxy blind, but at least equipped with prothean tech. When they encountered the Turians they were at least ready to push back a bit.

Batarian space is close to Alliance space, so, what if Earth was found by the Batarian hegemony or Batarian slavers first? Would they resist? Would earth be sacked or would the council intervene? 

Bonus: what if Turians discovered Earth? Would humans be made a client race?
gpt
Before humanity was on the scene, Batarians were in contact with the citadel races. They even had an embassy there; so if the Batarians tried to keep it secret that they had made contact with a pre FTL civilization the Salarians would pick up on it soon after. More than likely a whistle blower would emerge out of the spy network and alert the Asari and Turians of the Batarian's intent. 

So there is really no chance a Batarian slaving outfit would be successful longer than a matter of weeks, if at all. Keep in mind we aren't exactly defenseless, even with out mass effect weapons. We most likely couldn't defeat their ships but any ground action would not go unopposed. 

As for the second question, it's unlikely we would become a client race for the Turians. Our culture and even our nature is too motivated toward freedom and independence. We also have a long history or warrior culture, which would make the Turians possibly seek volunteers to join their forces or out source wet work to us until our own space infrastructure was up and running. Mercenaries would probably be one of the most common jobs to find humans working in for some time; hell most mercenaries companies you fight in the games are still mostly human.

Seeing how there are 7ish billion of us now and a solid percentage of us are educated, some even highly, introduction of mass effect technology would probably make us a moderate player in galactic affairs within 50 years of first encountering it, be it from an alien race or stumbling across it ourselves.