Two centuries ago, the Peninsulari, the residents of a peninsula were ruled by a Half-elven (Edain) King on a distant throne. He cared nothing for the human subjects who made up the eastern border of his kingdom for he was forever meddling in the affairs of the elven lands. The humans of the Peninsula wree left to pay tribute but gained no protection from the Army of the Green.
There was an upset in succession, and the Kingdom was thrown into a civil war as several generals and lords fought with one another to see who would become the next King of the Green. The Peninsula was called upon by several factions to levy troops. The seven district lords of the Peninsula drew together a meeting and decided that now was the time to make a stand for freedom from the distant tyrant.
Each wore a special ring forged at the same time by the most skilled smith in the peninsula, binding the will of the land, and the blood of the lord together in a ring. The rings were distributed to each lord, and each was used as a symbol of human freedom in the short series of battles that followed as the few loyalist militias were cast out of the peninsula.
There was a retaliatory war, but the Peninsulari were well prepared, and the Army of the Green was exhausted from a long civil war. The seven lords won freedom for the Peninsula and created the first republic in a land of Kings.
A Ring of the Arch-Duke cannot be worn by anyone other than a blood relation of its first wearer. Thus, if a hopeful lord could not wear the ring, he does not have the lineage to rule.
So long as he is on his home ground, the land dedicated to the Ring/First lord, the wearer is immune to magical fear, and has his ability to lead men increase, as well as a great reserve of willpower.