The country of nationality is the most difficult to rank in the world.

The Vatican covers an area of about 0.44 square kilometers and has a population of about 800 according to United Nations statistics. Among them, citizens are almost people who live in the Vatican because of their work or duties, including cardinals and diplomats of the Holy See.

2. Bhutan

I believe many readers are interested in Bhutan, which is known as the happiest country in the world. But in fact, it is very difficult for ordinary people to immigrate to Bhutan. Bhutan, with a population of about 800,000, is one of the countries with the lowest population density in the world and a relatively closed country.

3. Switzerland

Switzerland is the first and oldest permanent neutral country in the world. According to the national image ranking published by Simon Anholt, a British political scientist, and Ipsos, a polling agency, Switzerland ranks seventh, ranking among the best in terms of quality of life, investment, immigration and education level.

4. Liechtenstein

As one of the richest countries in Europe, Liechtenstein has a strict immigration policy. You can only apply in three ways.

5. Qatar

Qatar also has a strict immigration policy. At present, there are two ways to immigrate to Qatar: born in Qatar and parents who are Qatari citizens will automatically obtain citizenship, but the following two situations are broken down. If only the father is a Qatari citizen, he can apply for naturalization as long as he meets the qualification test.