The term sovereignty is derived from a Latin word ‘Superanus’ which means supreme. It, therefore, implies the supremacy of the state internally and externally.
Sovereignty is the most important characteristic which distinguishes the state from all other associations and its concept lies at the basis of the modem political science since it explains the relation between state and state and between state and citizens.
The concept of sovereignty, like so many other concepts, is the result of historical evolution. In his theory of classification of slates, Aristotle located sovereignty in one or a few or many. The Romans traced sovereignty in the emperor.
Feudal order of the middle ages destroyed the notion of single ultimate determinate sovereign power which lies at the basis of modern conception of sovereignty since feudal society was divided into hierarchy based on the ownership of land. Later, under the impact of commercial industrialism, sovereignty was vested in the hands of a king or an emperor instead of division of sovereign powers among the emperor, the king, the feudal lords, the tenants-in chief etc. Highly centralized governments were then established in most of the countries of Europe.
Bodin, in modem times, gave for the first time a philosophical exposition of the theory of absolute, unlimited and inalienable sovereignty. He defined sovereignty as the supreme power over citizens and subjects unrestrained by law. Hobbes developed a conception of legal sovereign.
He defined sovereign as ‘Leviathan’, i.e. absolute, final, omnipotent and Omni competent, his commands being law and citizens owing a duty to obey these laws. John Locke, developed the theory of the sovereignty of the people and clearly distinguished between political sovereignty and legal sovereignty.
Rousseau developed the conception of popular sovereignty. Austin gave the concept of legal sovereignty. He defined sovereign as a determinate human superior and law as his command.