To start let me say that I have only recently discovered the Birthright game, and have not yet (nor do I plan to any time soon) explore any 3.X iterations of the game.

At first glance Birthright appears to be one of the greatest roleplaying games/settings ever. But after looking at it more it began to dawn on me just how huge of a task it must be to run. Even if the DM restricts players to realms in a localized area the number of key actors on the scene whose plots, goals, and motivations that must be accounted for are dizzying.

For example the DM announces that all the players will play regents from the Southern Coast. Players being the pesky creatures that they are will no doubt have schemes that involve their neighbors outside of the Southern Coast (and key NPCs outside the region seem to want in as well). This will mean that Ghoere, Endier and Osoerde will factor prominently in this game.

That means there are 39 regents that have holdings in these realms, assuming that four of them are players that leaves the DM to plan for 35 regents every turn.

While the BRCS Rulebook suggests only having three NPC regents act a turn, and just updating inactive realms every once in a while, I can't imagine that working well without the world seeming horribly static despite all descriptions to the contrary.

In your experience how does a DM make the world turn without losing his mind?