I am not even kidding the Starwars universe has NO idea where humans came from.
Well I could tell you, but the details are kinda messy.
According to the Wiki a lot of theories have been presented but never a Affirmation.
The current theory is that the human homeworld is somewhere near the center of the galaxy.
I wonder if the human homeworld is earth... and if it is... how did they get to a galaxy far far away when NONE of the current technology gives transgalactic flight (add in that this isn't a Far away Galaxy... this is a FAR FAR away galaxy... and yeah)
Ok... NO you have to tell me because this question is too perplexing.
"The "Long Time Ago" thing was from the point of reference from someone (or something) far in the future"
Naw, its from us. Otherwise it would make no sense. Mind you if I am to believe Soul Calibur... then Episode 1 takes place in the 1600s
"who spread them around before dying out"
The actual information is a lot more confusing then this. For example humans developed their own space flight, but records show that before this they were on multiple planets. As well records show that they existed FAR beyond the precursors domain.
or whatever happened to them- I do not recall their eventual fate
They became immune to mitoclorians and thus their technology couldn't be used (as they all required the force to be used).
I liked the Mitochlorians back when I thought they were actually a bacteria that existed on people who had the Force... not when it was actually the source of the force (Ignoring that it isn't the only way to get the force)
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Also my theory is that they were taken from Earth by a FAAAAR more supperior race to anything that has ever been shown in Starwars. Afteral Transgalactic flight.