The Runners of Meldan

What keeps the kingdom of Meldan as one is neither the crown, nor the royal guard, nor the clergy, but the Runners.
The Runners of Meldan are a fleet of riders tasked with delivering news, decrees and other information between different parts of Meldan, and particularly with the dissemination of information from the royal capital, Meldan-ty-Kerth, to the citizens in the rest of the country. 
Although the Runners are technically a part of the royal army, they are usually only given a very basic degree of military training, and are generally not armed beyond a foot-long, mostly decorative knife at their belts. The exception to this is the Spear Runners, a specialist troop of Runners that deal in the delivering of military messages and commands during times of active combat.
The characteristic livery of the Runners consist of a cream-colored shirt and hose, worn under a dark blue sleeve-less tunic on which the insignia of the Runners, a horse in full gallop, is embroidered in silver thread. Black boots and riding gloves are also part of the livery, and a hooded cloak in the same dark blue and silver are used in rough weather. Wearing Runner livery if you are not a Runner is considered a form of fraud.
If something should happen to a Runner's horse, or if it is simply been ridden too hard to continue, the Runner has a legal right to seize the horse of any person in the country in order to carry out their orders. Refusal to comply with this is punished severely, either by hefty fines, the seizing of horses and other property or even by imprisonment. The punishment generally depends on the relative importance of the message that the Runner was delivering. Although it is a legal requirement to do so, a citizen who gives up their horse to a Runner is usually rewarded, if not by the crown then by their countrymen.