Third Indochina War: Causes & Effects

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Postwar Relations Between America and Vietnam

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:03 Vietnam: Yesterday & Today
  • 0:48 Cambodian-Vietnamese Tensions
  • 2:25 Vietnam Invades
  • 3:22 China Gets Involved
  • 4:30 Effects of the Third…
  • 5:18 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed
Lesson Transcript
Instructor: Christopher Sailus

Chris has an M.A. in history and taught university and high school history.

Right after the Vietnam War, another war broke out in the region that involved Vietnam, Cambodia, and China. In this lesson, we'll explore the series of interconnected conflicts that followed on the heels of the Vietnam War, known collectively today as the Third Indochina War.

Vietnam: Yesterday & Today

Today, Vietnam is a relatively peaceful place. With delicious food and friendly people, Vietnam is considered to be relatively safe. Even the U.S. State Department currently states that the potential threat to U.S. citizens while in Vietnam is low. Visiting Vietnam today, one might be surprised to learn that it spent most the second half of the 20th century in varying states of warfare. The Vietnam War, for instance, began in the late 1950s and continued through the early 1970s, and claimed the lives of more than 55,000 American servicemen and women and countless thousands of Vietnamese. But peace wasn't to be just yet. Right after this, the country entered into more conflict, known as the Third Indochina War.

Cambodian-Vietnamese Tensions

After the fall of Saigon in 1975, Vietnam was truly united under the communist flag. Unfortunately, even as Vietnam was sewing itself back together, tensions were mounting with its neighbor, Cambodia. Cambodian-Vietnamese relations deteriorated for several reasons. Relations between the two governments were initially friendly, as the Cambodian government was ruled by the Khmer Rouge, Cambodia's Communist party, led by Pol Pot. But in the months and years immediately after the fall of Saigon, a series of incidents along the long Vietnam-Cambodia border ignited tensions.

For example, the day after the fall of Saigon in 1975, Cambodian troops seized a small Vietnamese island. Though the Vietnamese quickly retook the island, hundreds of Vietnamese citizens were massacred by the Cambodian army during the island's occupation. This incident is representative of a larger negative policy toward ethnic Vietnamese in Cambodia under the Pol Pot regime. Vietnamese were routinely persecuted by Cambodian authorities.

The Vietnamese and Cambodian governments grew deeply distrustful of one another. Vietnam viewed Cambodia as China's pawn. In fact, it saw Cambodia's very presence, which is along Vietnam's border, as a fundamental threat to Vietnam's sovereignty. Cambodia's government resented what it viewed as Vietnam's paternalistic attitude toward Cambodia, and as a result it did little to stem cross-border raids made by rogue Cambodian forces. It didn't help that Vietnam had been aiding Cambodian dissidents who wanted to overthrow the Khmer Rouge. In fact, this drastically damaged relations between the two countries.

Vietnam Invades

In February 1978, Vietnamese leaders made the decision at a secret meeting to invade Cambodia. The ensuing months saw a foreign relations and diplomatic blitz on the part of Vietnamese leaders to discredit Pol Pot and Cambodia. The Vietnamese government hoped that by painting a poor picture of Pol Pot and Cambodia, the international community would be less likely to intervene in a Vietnamese invasion. This effort was aimed at the entire world, but particularly at China, who was formally allied with Cambodia.

The strategy worked. In June, approximately 80,000 Vietnamese troops crossed the border into Cambodia unopposed with air and military support in a full-scale invasion of the country. The Vietnamese army easily overran the Cambodian forces, capturing Phnom Penh, the capital, and deposing Pol Pot's government. The Vietnamese occupied Cambodia for more than 10 years before withdrawing back across its own border in 1989.

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