Is there any indication in canon that there were
post-Ancient/post-Final-War starfaring civilizations, especially human
ones, prior to the Vilani and Zhodani appearing on the scene?
Dear Jeff,
Glancing through my Timeline Addendum ...
-200,000c
TL 17+ structures built on Balzac (1636 Deneb) by a presumably local sophont culture. [MgT: Deneb Sector]
-100,000c
The Sulliji of Catacomb (2234 Deneb) are at TL16, but without jump drive. [GURPS JTAS]
-65,000c to -49,000c
Hhkar civilisation, though using STL travel, manages to settle the stars and engage in interstellar civil war. [GURPS Aliens 4; GURPS JTAS]
-57,000c to 15,000c
The now-extinct Kurakhash establish a small interstellar empire. [MgT: Deneb Sector]
-9240
Geonee develop jump drive, 5 years before the Vilani, after having found a derelict starship 30 years prior. Geonee expansion continues for 250 years before contacting another FTL-capable civilisation (the Vilani). [GURPS Humaniti] Looking at other sources, it is a few thousand years before these two civilisations are seriously competing and, by that stage, the Geonee have munged themselves in a civil war that ended their commitment to a centralised pan-Geonee government.
That's all the general high-tech references I have, nothing else about FTL travel for fun-and-profit specifically.
Cheers,
KenB