The Colloquium of Progress was an expansive, peaceful multispecies community that existed eighteen millenia prior to the 24th century, by which time it was unknown. Among the member races were the Caratu, the D'drauk'k and the Talich. (DTI novel: Watching the Clock)
In that era, the Colloquium maintained the Colloquium of Progress Outpost in the Axis of Time. The Axis allowed the Colloquium to learn that their society would be forgotten in the future, and was an opportunity to interact with civilisations from millions of years uptime and downtime.
Inside the Axis, the Colloquium had a representative on the Axis Council. In that capacity, Councillor Oydia made first contact with the United Federation of Planets from the year 2382, a similarly multispecies society.