The Orion Congeries were an organization of "nonaligned" planets that were rivals in trade with the Inshai Compact, which resisted their expansionist aims. They were suspected of placing an (alleged) sunkiller bomb in the star Sigma-1014 Orionis, causing it go nova and destroy the hearthworld of the Inshai Compact.

The Decipher RPG module: Player's Guide places the birth of Surak in 279 CE, while the TOS novel: The Romulan Way places it circa 67 BCE. Subtracting the distance in light-years between (the fictional) Sigma-1014 Orionis and 40 Eridani (Vulcan's sun) from either of these dates would give the true date of this event. Both novels imply forty-five years or less.

This destruction quickly led to the collapse of the Inshai Compact, along with its great power and restraining influence. The Orion Congeries swept in to begin their long-desired piracy, and war, famine, plague and economic and social collapse swept the Compact worlds. Meanwhile, decentralized interstellar corporations of the Compact seized power, armed with planetcracker weapons, fighting over trade routes and sources of raw materials, blackmailing worlds into submission and destroying those who didn't. Formerly peaceful Compact worlds, like Etosha, and depopulated ones, like Duthul, fell into this kind of piracy to survive. These worlds and corporations degenerated into the guilds and companies that were the direct ancestors of modern Orion pirates. (TOS novel: The Romulan Way, TOS novel: Spock's World)

In both sources, it is said that the Orion pirates evolved out of the Inshai Compact, but also that it was the Orion Congeries that attacked the Compact in the first place. Thus it is not clear what species were in the Orion Congeries, or if the Etoshans, the Duthulhiv and others were themselves Orions or some other race. They may be some of the non-Green Orion races seen in some sources.
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