With the war put on indefinite hold, the four universal civilizations began official work, first and foremost, divvying territories.
Recognized as rulers of the universe, they divvied up all known star fields amongst one another.
They then created laws for all other civilizations to govern with and abide by, before setting up the basic blocks necessary to ensure their reign.
Such as laws, trade routes, and a universal currency. Thus inadvertently connecting the star fields with one another.
With the universe now connected with one another, slowly but surely, a market formed as trade and travel routes were established.
A market that went beyond all boundaries, signalling the start of the interstellar era.