The Galactic War was the single most devastating and widespread event in the history of my UIIverse. It was a long and very destructive war between humanity and most of the major races in their vicinity in the Milky Way Galaxy, including the Ashvani and Koror. It lead to billions of deaths and star-spanning destruction.
The Galactic War was ended by the realignment of alliances among the warring empires. It officially ended with the signing of a Galactic Treaty, which ushered in a new period of peace, rebuilding, trade, and eventual prosperity which is the usual “now” in these UIIverse stories.
There are military stories that occur during the war years, such as the Watchtwer tales. There are stories that occur in the aftermath, such as the tales of Sharlokh and Dr. Watt-ZENN. Many other stories may simply reference it.