The modern theory of sovereignty was popularized by

The modern theory of sovereignty was popularized by Jean Bodin. He was a French political philosopher who lived in the 16th century and is considered one of the founders of modern political science. In his work "Six Books of the Republic," Bodin defined sovereignty as the supreme and absolute power within a state, belonging to the people or the ruler, and not subject to any higher authority. This idea of sovereignty as a central and supreme power within a state became widely accepted and is still considered a cornerstone of modern political theory.