Since previous to suikoden 3, there was a ball celebrating the 50th anniversary of Zexen, I think this abit suspect.A mercantilistic nation that used to be a part of Grassland, but seceded from Grassland to form a new nation 20 years prior to Suikoden III.
420 - Zexen Established
Zexen Confederation and Knights are formed. Construction begins on Brass Castle.
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470 - Zexen 50th Ball
50 year anniversary of the foundation of the Zexen Federation. A large celebration is thrown, where two prominent young women - Lilly Pendragon and Chris Lightfellow - get into a big fight, causing much amusement for all others in attendance.