Government: Council Of Leaders
The Undermountain kingdoms are collectively considered the kingdom of “Gunder Thorn”. They are situated in a vast network of caverns and engineered transport-ways throughout the Cragmoor Mountains, linking all cities and towns of the Dwarfish kingdoms together. The major cities have the most advances methods of transportation, with smaller less central cities having slower or no constructed transport systems. The Dwarves have developed (with the help of many Gnomish engineers) some of the most advanced railway, and tunnel-running systems in all of Valenthal, Most of the travel from one major city to another is done at speeds in excess of 45MPH, however there is a price to pay for high speed transport. The injury and casualty rate for Undermountain travel is much higher than most other forms of transport.
Fast transport subways, driven by water, steam and gravity locomotion, connect the 4 Major Dwarfish kingdoms. These routes rarely have mechanical breakdowns, and are the fastest of the transport ways in the Undermountain.
The Thanes of all four of the major cities, and the Clan Heads of each of the 11 clans rule the Undermountain. These 15 dwarves make all decisions for the Undermountain kingdom, and set the policies of their people. The council of leaders meets for several days every four months (really this ends up being an excuse to declare how important they each are, then get roaring drunk for a couple days). Any three members can declare an emergency session, not showing up to an emergency session is considered very bad face (and usually a personal affront to those who called the session)
Non-dwarves are not allowed to move into one of the major cities unless they get a pardon from the office of the Thane (not as difficult as it sounds, but being caught without one, will get you ejected off the nearest cliff).
Much of the trading that Dwarves of the Undermountain do, is at posts that the Dwarves have set up above ground in the valleys bordering the Mountains, and in Trastenhoff.