Sovereignty is an essential element of the state. State cannot exit without sovereignty. State is regarded superior to other associations only because of sovereignty. In fact modern theory of state got its proper shape and perfection only when the concept of sovereignty was introduced in it.
When we try to search for the origin of this concept we find that he term sovereignty is the product of modern political thinking but the idea goes back to the time of Aristotle who referred to it as the “supreme power” of the state. In Middle Ages Roman jurist and civilians were also familiar to this idea. But it was Jean Bodin who developed for the first time the theory of sovereignty systematically in his book “Six Books on the Republic”.
Meaning, nature and definitions:
The term sovereignty is derived from the Latin word ‘Superanus’ meaning supreme. It is basically a legal concept. It denotes supremacy of state. To understand the term sovereignty, it is desirable to look into some definitions of the given by some political thinkers.
Jean Bodin defined sovereignty as “absolute and perpetual power of commanding in a state. It is supreme power over citizens and subjects unrestrained by law”.
Pollock says that “Sovereignty is that power which is neither temporary nor delegated nor subject to particular rules, which it cannot alter, nor answerable to any other power on the earth.”
Burgers described sovereignty as “original absolute unlimited power over the undivided subjects and over all associations of subjects. It is the underused and independent power to command and compel obedience.”
D.F Russell defines sovereignty as “the strongest power and supreme authority within a state, which is unlimited by law or anything else.
Distinction is some times drawn between legal and political sovereignty. The sovereign is supposed to be absolute and omnipotent. It functions according to its own will. Law is simply the will of sovereign.
There is none to question its validity. Legal sovereign grants rights to its citizens and there can be no rights against him. It means rights of citizens depend on the will of legal sovereign and any time he can take away. Legal sovereign has following characteristics-
1.The legal sovereignty is always definite and determinate.
2.Legal sovereignty may reside either in one person or in a body of persons.
3.It is definitely organized, precise and known to law.
4.Rights of citizen are gift of legal sovereign.
5.The will of state is expressed by the legal sovereign only.
6.Legal sovereignty is absolute. It cannot be question.
In Britain King in Parliament is the sovereign.  In U.S the legal sovereign consists of the constitutional authorities that have the power to amend constitution. But behind the legal sovereignty there is another power, which is unknown to law. It is political sovereignty. In practice absolute and unlimited authority of the legal sovereignty does not exist anywhere. Even a dictator cannot act independently and exclusively. The will of legal sovereignty is actually sharpened by many influences, which are unknown to law. All these influences are the real power behind the legal sovereign; and this is called political sovereignty.
Austin’s theory of sovereignty (monistic view)
In the 19th century the theory of sovereignty as a legal concept was perfected by Austin, an English Jurist. He is regarded as a greatest exponent of Monistic Theory. In his book ‘Province of Jurisprudence Determined (1832) Austin observed’ “if a determinate human superior, not in the habit of obedience to a like superior, receives habitual obedience from the bulk of a given society, that determinate superior is sovereign in that society and that society (including superior) is a society political and independent.” To Austin in every state there exists an authority to which a large mass of citizen show compliance. This authority is absolute, unlimited and indivisible.
Austin’s theory of sovereignty depends mainly upon his view on nature of law. According to Austin “Law is a command given by a superior to inferior” the main tenets of Austin’s theory of sovereignty are as follows-
1. Sovereign power is essential in every political society.
2. Sovereignty is a person or body of persons. It is not necessary that sovereign should be a single person.
Sovereignty may reside in many persons also. Austin explains that a “Sovereign is not necessarily a single person, in the modern western world he is rarely so; but he must have so much of the attributes of a single person as to be a determinate.” To Austin state is a legal order, in which there is a supreme authority, which is source of all powers. Sovereignty is concerned with man, and every state must have human superior who can issue commands and create laws. Human laws are the proper subjects of state activity.
3. Sovereign power is indivisible. Division of sovereignty leads to its destruction. It cannot be divided.
4.The command of sovereignty is superior to over all individuals and associations. Sovereign is not bound to obey anyone’s order. His will is supreme. There is no question of right or wrong, just or unjust, all his commands are to be obeyed.
5.Austin’s theory says that the obedience to sovereign must be habitual. It means that obedience should be continuous. He also includes that is not necessary that obedience should come from the whole society. It is sufficient, if it comes from the lay majority of people. Obedience should come from bulk of the society otherwise there is no sovereign.
In brief we can say that sovereignty according to Austin is supreme, indivisible and unquestionable. Like all other theories of sovereignty Austin’s theory is also not free from criticism. The first criticism is regarding sovereignty residing in a determinate superior. Even sovereign’s acts are shaped by so many other influences, such as morals, values and customs of the society.