The "empire" was originally a reorganization of the Confederation of Enat (which in turn evolved from the League of Enat), which greatly increased the power of the central government and created a true federal/state system rather than the previous collection of autonomous small states.
The empire was multi-national, including both the states around the Sea of Enat who all belonged to the ethnic group which are now called Elosians (although this term was not so used then) and spoke the Elosian Language; but also such others as the Manultulians and Haltickch.
The head of state was known as Elockantan (emperor), Atricksantan (all powerful), Parspimantan (leader in the worship of the gods), and Renogladantan (supremely honorable).
The states were represented in a legislative body called the Assembly, which existed from the days of the Conferation. The states had a diverse variety of governments and means of choosing their delegates in the Assembly.
In the early years of the empire, the emperor had near-absolute power and the Assembly largely served to ratify the emperor's decisions. Binalon I, the first emperor, was awarded his title by an Assembly that was already firmly under his control.
Later emperors allowed their cabinets and advisers to have greater power, until the position of emperor was almost entirely ceremonial. The real head of government was a position shared by about five men known as the High Council. This state of affairs is thought to have begun as early as the second century EYE, but was not widely known until the reign of Andria, 368-398. Mondroy the Younger temporarily regained absolute power, but after 408 the Council regained control permanently.
Gradually, the power of the central government declined and the power of the states began to re-assert itself. By 1000 it had become somewhat common for states to maintain their own armed forces. There came to be wars between states, and confederations of states that came to resemble empires within empires.
In 1348, the empire was suddenly invaded by a coalition of Vians, Tijils and Erctilians. The nearly-powerless central government collapsed instantly. In 1349, the newly organized Stofonian Empire conquered all, claiming to be the divinely ordained replacement for the Elosian Empre.