Officially, the Empire is ruled by Emperor Ryushen, the 142nd ruler in an unbroken Imperial line extending back almost 4,000 years. He administers his laws and policies with the aid of the Imperial Bureaucracy, a meritocratic hierarchy of scholars, lawyers, and, well, bureaucrats.
In actual fact, the Empire is governed through a delicate, dynamic and unwritten power-sharing arrangement between the Bureaucracy (led by the Emperor) and the warrior class, led by the Shogun. The power of the warrior class is based on their monopoly on military force. The Emperor, on the other hand, has three sources of power:
1. Perceived legitimacy – millenia of tradition count for a lot with the people of Yamato; an Imperial line that has remained unbroken for almost 4 milennia would be very hard to overthrow.
2. Magic – arcanists must either be affiliated with a temple or the Mage’s Guild; the Guild is part of the Bureaucracy. This means that the Emperor commands most of the arcanists in the Empire.
3. The dragon Shendokai – an ancient gold dragon who helped the first Emperor, Takashi, unite the 4 islands and found the Empire of Yamato. He sleeps (or at the very least, remains unseen) most of the time, but responds to the summons of the Emperor. On the few occassions when an ambitious Shogun has attempted a coup, the appearance of the dragon has turned the tables and quickly dispersed the rebel army.