It's called conquering
It is called annexation when one country takes over another country and incorporates it into its own territory without the consent of the other country.
It's called conquering
It is called an invasion.
It is called annexation when one country takes over the land of another. This can happen through various means such as military conquest, treaties, or agreements between nations.
A foreign occupation is when Another Country invades and takes over another county.
to conquer
When a larger country takes over and controls a smaller territory, it is called colonization or imperialism. This often involves political, economic, and social dominance over the colony by the colonizing country.
socialism
It is called annexation or intervention when one government takes control over another forcibly or through other means, often leading to political or territorial changes.
It is called a takeover. If the other company is taken over against its will, it is called a hostile takeover.
In the context of the Cold War, yet generally true for any context, the take-over of Another Country (or region belonging to another country) is usually called a 'conquest.' Where it is accomplished without fighting, one may refer to it as an 'annexation' or, in certain circumstances, a 'usurpation.' If the land in question is not formally claimed or organized, its take-over may be variously put as a 'claiming,' a 'discovery,' or 'occupation,' among other terms available.
That is called imperialism or colonization. It involves one country exerting political, economic, and cultural control over another country or region. Imperialism can also refer to the dominance of one religion over others within a society.