Study the basics, concepts, and codes of citizenship of foreign nationals

Citizenship is a legal relationship; because it has legal effects on the international and internal systems. The country's nationals enjoy their government political patronage in the international system. The goal is to study the basics, concepts, and codes of citizenship of foreign nationals. The methodology is analytical-descriptive and uses library resources. It investigated the concept of citizenship, defining nationals, citizenship elements, defining residence, attending foreign in Iran, and their legal situation. The investigations showed that the local law allows the government almost in all countries to deport foreign nationals whose residence seems undesirable whenever it wants. Of course, any government should not suddenly deport all foreign nationals residing in its country. Deporting all foreign nationals from its country is considered a wavering government and acts opposite of the international expediency. The government should not only decide to deport all foreign nationals but deporting suddenly all foreign nationals is against international legal basics; this action can do so during the war and break up political relationships.