According to the principle of self-determination, peoples have the right to sovereignty, which is divided into internal and external self-determination. Internal self-determination is manifested in the right to cultural, social and economic development, while external self-
determination is most evident in the right to form one's country and to act as a sovereign entity in the international legal space.
The theory was developed in international documents after the end of World War II by the UN, which recognized internal self-determination for all peoples while restricting external ones to colonial peoples and defining a very narrow interpretation in their definition. The
second half of the 20th century, in turn, brought about the emergence of a huge number of new countries, especially in the African and Asian continents.
More or less all central governments are confronted with the existence of a group or groups of people with different cultural, linguistic and social characteristics. The approach of each central government to these groups of people is different, but over the last hundred years, it
can be observed that they have more of an ear for their needs and for recognizing different forms of self-government. Central governments sign international agreements with them and adopt them into constitution.
Theory knows two different constructs that seek to explain the remedial right to self-determination, that is, the unlawful right to secession, which is to remedy an unjust state. The task under scrutiny takes the remedial right to secede Allen Buchanan. Buchanan recognizes the right of people who are severely oppressed by the state, and secession would mean a remedial action.
Catalonia has been part of the Kingdom of Spain for centuries. Under the Spanish Constitution, it has the status of an autonomous region, on the basis of which it has specific rights. It is almost impossible for Catalans to recognize the right to external self-determination
under international law, which is not favored by the Spanish Constitution. The unrest of the last decade suggests that something is not right in Spain, so any solution must be sought in theories such as the remedial right to self-determination.