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Overview of the Eberron Campaign Setting
The tone of Eberron is post-war high-fantasy action-adventure. The land is inundated with soldiers back from the war who are not sure what to do with their lives. The different nations are in an uneasy peace and eying one another suspiciously.
Khorvaire, was once a single unified human empire called the Kingdom of Galifar. Galifar was founded nearly a thousand years ago in 1YK and would have lasted a thousand years if not for a war of succession that plunged the whole continent into disarray. The greatly diminished borders of the Five Nations, Cyre, Aundair, Breland, Thrane, and Karrnath are what remain of that empire. The remaining nations are younger political entities that represent mainly non-human interests: Valenar for the elves, Mror Hold for the dwarves, Zilargo for the gnomes, the Shadow Marches for the orcs, Droaam for minotaur, ogres, and medusa. All nations now upon Khorvaire have been recognized by the Treaty of Thronehold, 996YK, which marked the end of the Last War. All nations except for Cyre. It was destroyed in a mysterious explosion that blanketed and destroyed the entire nation, known as The Mourning.
South of Khorvaire is Xen’drik, an unexplored jungle continent where an empire of giants once ruled. East is Sarlona, the strange homeland humanity fled from over a thousand years ago. South-east is Argonnessen, home of dragons and dragon-worshiping barbarians. Frostfell and Everice are at the north and south pole of the world.
Life on Khorvaire involves great amounts of everyday magic. The populace travels across continents and between towns via elemental railways and flying airships, and communicates with one another through an elaborate and reliable magic postal service. Great metropolitan cities and magnificent structures are made possible through magic construction, and the people count sentient golems (The Warforged), former tools of war, as citizenry.
There is much to marvel at in Eberron, but that wonder is tempered by the raw wound left by the Last War, the war you will experience first-hand.