Self-determination of the peoples in a specific state or land supersedes all historical claims of sovereignty, if it goes contrary to the wishes of the natives. This is the norm governing international law, as defined by the UN Charter and the Geneva Conventions. Anything that goes against this spirit is usually seen as colonization, which is something that is continually being deconstructed after World War II.
Self-determination denotes the legal right of people to decide their own destiny in the international order. Self-determination is a core principle of international law, arising from customary international law, but also recognized as a general principle of law, and enshrined in a number of international treaties. For instance, self-determination is protected in the United Nations Charter and the International Covenant on Civil and Political Rights as a right of “all peoples.”
The scope and purpose of the principle of self-determination has evolved significantly in the 20th century. In the early 1900’s, international support grew for the right of all people to self-determination. This led to successful secessionist movements during and after WWI, WWII and laid the groundwork for decolonization in the 1960s.
Contemporary notions of self-determination usually distinguish between “internal” and “external” self-determination, suggesting that “self-determination” exists on a spectrum. Internal self-determination may refer to various political and social rights; by contrast, external self-determination refers to full legal independence/secession for the given ‘people’ from the larger politico-legal state.