Revolutionary social changes have led to reformations in the constitutional system of countries in human history. In this sense, Constitutionalism has had a direct impact not only on the countries and their people, but also on the lives of the mankind as a whole. Constitutionalism in the modern sense, a concept that is based on a society in which people are the masters of their own and that guarantees human freedom and rights, originates from the American Revolution of 1787 and the French Revolution of 1789. The bourgeois revolution brought about a fundamental social transition from monarchical sovereignty dominated by absolute monarchies to popular sovereignty. Modern constitutionalism has gone through many kinds of “challenges and responses”. Firstly, the industrial revolution of the 19th century led to the Proletarian Revolution. In the 20th century, after World War I, the world was split into people's democracy and liberal democracy. After World War II, the world was divided even more sharply. After the fall of the Berlin Wall in 1989, however, communist people's democracy virtually came to an end. In the early 21st century, as the 9/11 terrorist attacks made a new inflection point, the traditional legal system and legal theory also brought about fundamental changes. In addition, with the progress of the intelligent information society, drastic changes are coming to human life.
 The Constitutionalism which is resulted from gradual social reform in Britain and radical social reform in the United States and France, has been the model one for other countries in the world. Yet, the establishment of Constitutionalism is still far away in the Middle East and Africa. Constitutionalism in Latin America also remains unstable. Constitutionalism in Asia is entering a stable stage in many countries. The discussion on whether globalization of Constitutionalism, “Global Constitutionalism”, is feasible, will be enabled only by considering both the current situation of the human world and the present status of individual Constitutionalism in each country simultaneously. As each country is developing its own Constitutionalism, global Constitutionalism must substantially guarantee the freedom and rights of each members of people based on popular sovereignty. Since the actual meaning of Constitutionalism very diverse in each country and the essence of Constitutionalism, in some country, could be seriously distorted, Global Constitutionalism is still far away and its implementation is also unclear.
 Unlike the nature of revolution, Constitutionalism is an ideology that is established on the continuity of history. People should internalize constitutional values for the success of Constitutionalism. It is time to develop a theory based both on a general understanding of foreign constitutional theories and on the norms and reality of Korean Constitution. In other words, while being based on modern natural law theory that is the common value of the modern constitution, it must be based on legal existentialism which recognizes and adapts to the existential legal norms and legal realities that are unfolding in Korea. By doing so, a theory of balance can be established in the understanding and practice of constitutional law through the harmonious development of legal ideology and legal stability that are sought to be established in the contemporary era. Only when the Constitution, the country's basic law and highest law, is implemented in the country and breathes with the people, does the Constitution become the “people's charter for life.” At that time, the Constitutionalism of a democratic rule of law based on popular sovereignty can open the way for the rule of law to take root in the lives of the people.