The North Atlantic Treaty of 1949: History & Article 5

Instructor: Christina Boggs

Chrissy has taught secondary English and history and writes online curriculum. She has an M.S.Ed. in Social Studies Education.

After World War II, the United States and its allies in Western Europe were concerned about their security against the Soviet Union. This lesson explains the history of the North Atlantic Treaty of 1949 and Article 5 of the treaty.

After World War II

When World War II came to an end in 1945, the world breathed a collective sigh of relief. After six years of devastating destruction, Europe and Asia were finally given a chance to rebuild. On the surface, this appeared to be the case, but there were a number of underlying issues at hand. The United States and Soviet Union emerged from the war as the two dominant world powers. Neither country had suffered much damage and did not have to worry about rebuilding. At the same time, these two countries had very different visions for the post-war world. The United States pictured the spread of democracy, while the Soviet Union imagined the growth of communism.

Origins of the North Atlantic Treaty

The uneasy war-time alliance between the Soviet Union and the Western Bloc (made up of the United States and its Western allies) quickly fell apart after 1945. This led to the Cold War, a state of military tension that would last from roughly 1945 to 1991. During this time, Soviet Premier Joseph Stalin took many actions to promote communism in Europe, including staging a coup d'etat to overthrow a democratic government in Czechoslovakia. Stalin also cut off the Western allies from Berlin, Germany's capital. Both the United States and countries in Western Europe were very alarmed. A strong Soviet Union was a threat to both Western European security and U.S. interests.

Leaders of 12 nations sign the North American Treaty, 1949.
North American Treaty

In 1949, the United States and 11 other countries drafted and signed the North Atlantic Treaty. The treaty was a collective security agreement, or an alliance that was meant to increase the overall safety of each country from any sort of external threat. As a part of the treaty, the countries agreed to mutual defense. If any of the members came under attack, then the other countries promised to provide military aid. The North Atlantic Treaty formed the North Atlantic Treaty Organization (NATO). The original members included:

  • United States
  • Canada
  • Belgium
  • The Netherlands
  • Luxembourg
  • Italy
  • Iceland
  • Portugal
  • Denmark
  • Norway
  • United Kingdom
  • France

Article 5

Article 5 of the North Atlantic Treaty outlines the mutual defense obligations of member countries. First, the treaty outlines that countries are only obligated to come to each other's defense if an attack happens in North America or Europe. During the late 1940s, many of the member countries still had territorial claims or colonies around the world in Africa or Asia. If any of these holdings were attacked, members of NATO were not required to provide aid.

According to Article 5, if a member of NATO is attacked, the other members will view that attack as an attack on all member countries. In response, each member is required to help assist the attacked nation 'as it deems necessary,' including military force.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account