Yup! Obviously there were other founders (how does one federate oneself, exactly?) but I think humans are portrayed as being the main force behind it. I still thing it leans too far in the direction of being a one-species society but maybe if I had seen more stories showing the Federation's origins it would seem sensible? Or perhaps not. It has been many years since then.

<.<
>.>

I'm writing a post which features El Goonish Shive right now, actually.