What countries were bound to each other and by which alliance?

Countries are often bound to each other through alliances such as NATO (North Atlantic Treaty Organization), which includes the United States, Canada, and several European nations, committed to mutual defense. Another significant alliance is the European Union (EU), which fosters economic and political integration among its member states. Additionally, historical alliances like the Axis Powers in World War II included Germany, Italy, and Japan, while the Allies comprised nations like the United States, the Soviet Union, and the United Kingdom.