Nationbuilding: How People Move, Talk, Think, Organize, & Structure Themselves, 1888, Amsterdam University Press' Wrote:…when discussing the size of a state, it is important to remember that the effective limits of the size of any nation is based on four primary factors: the communications response loop, the information/decision-making effectiveness, law enforcement effectiveness, and social viewpoints on society size.
All of the large empires prior to the domestication of dragons were limited primarily by the communications loop factor; an empire's size is restricted by the distance a messenger can travel from the decision center to the periphery with orders and get back in a reasonable period of time. Various pre-dragon empires tried various means of extending this range; for example, Rome made use of its famous roads and Persia had the first post office, while China worked by decentralizing the provinces, but this did cause several civil wars over the course of their history as rebellious provinces attempted to break away.
The coming of the dragon courier, though, changed all of that, by significantly increasing the speed at which messages could travel; a horse courier on well-paved roads can travel at an average of 15-25 kilometers per hour, if they have ready remounts at waystations along the route. However, average speeds of 10-16 km/hour for horse couriers were more typical, especially away from main routes and their waystations. A dragon courier, in contrast, when flying one of the breeds used for courier duty, can reliably expect average speeds of 100-160 km/hour, potentially faster for shorter sprints, and needs no roads or waystations, with the primary limiting factor being the provisions needed to feed the dragon.
As a direct result of that event, the effective range at which a nation could be managed and organized, in the absence of the other factors, had effectively increased by an order of magnitude, and this had tremendous influence into shaping the world of today.
Changes in decision making, however…
That's right, it's time to find out what happened under the snow, and then above it, and as far afield as the First and Second Romes, as A Thing of Vikings continues:
https://archiveofourown.org/works/104089...s/31158480
https://www.fanfiction.net/s/12639117/39...Of-Vikings
(CW for Heather telling Cami exactly what her Alvin-style spy training involved, via discussion of torture techniques, bordering on offers/threats to demonstrate them, and of non-consensual sex displays.)