Germany
Korea into North and South.Germany was split east and west.
Japan
There are several possible answers. Korea, which was divided into North Korea and South Korea following World War 2. Vietnam, which was divided into North Vietnam and South Vietnam following the first Indochina war. Following the Vietnam War, they returned to being one country. India, which was divided into India and Pakistan (East Pakistan and West Pakistan). Later, Pakistan became two separate countries, Pakistan and Bangladesh.
capitalism and socialism
france,poland
Britain and France
United States supported South Korea after World War 2.
United States supported South Korea after World War 2.
Italy and France
No official reason was given for why India was divided after World War II. However, many see it as a divide and rule situation because India was two big to govern effectively.
What nation? Without knowing what country you are referring to, there isn't any way to properly answer this question.