That is called an 'Alliance' or a 'defence pact'
That is called an 'Alliance' or a 'mutual defence pact'
vassals. Vassals were appointed by a lord to protect him in exchange of land.
When you leave a country it is called emigration.When you arrive in a country it is called immigration.
A person who comes from another country is called an immigrant.
A country that is a 'friend' of another country is called an ally.
The movement of people from one country to settle in another country is called immigration.
its called nationalism or, it could be colonization.
When a company hires people in Another Country to do work for them, it is called outsourcing.
When people leave their country to live in another country, it is called emigration.
When a company hires people in Another Country to do work for them, it is called outsourcing.
It's called conquering
A person who leaves a country to go live permanently in another is called an emmigrant,