Nature Of International Relation:

International relations emerge during the 1920s. Since it was considered a discipline within political science. The reason for that is that it is largely depending on political science and history. This controversy seems to have died down in the 1960s and IR was recognized as an independent academic discipline. Independent academic discipline requires a systematic body of theory, methodology, and a distinct subject matter. International relation is capable of all of these criteria to be called an autonomous academic discipline. This controversy does not exist anymore.

We knew that political science is concerned with the polities of a state (formal and informal). For example, the USA, UK, France or Egypt, etc. International relations is concerned about the relations among these states or relations between two of them. These relations may not be limited to just political aspects but will also include other aspects such as environmental issues, economic, cultural, and security issues, etc. IR scholars will not only just study the political system of a state (country)  or the constitution of a country but also the relations of a state with another state. Political scientists are more interested in the Government of a country, its internal politics, and political party system. But IR scholar is more interested in the foreign policies of a country and their impact.

This does not mean that both are absolutely separate. Both scholars can study each subject for clarification and academic work. The separation is meant to bring ease in studying and make it more effective and understandable.