Lesson Plans: Grades 9-12

Lesson 1: Postwar Disillusionment and the Quest for Peace, 1921–1929

A We The People Resource


The Lesson


Senator William E. Borah, (R-Idaho), was a prominent American isolationist who  gave a speech on "outlawing war" in 1924.

Senator William E. Borah, (R-Idaho), was a prominent American isolationist who gave a speech on "outlawing war" in 1924.

Credit: Image courtesy of American Memory at the Library of Congress.

Go to the related interactive

America on the Sidelines: The United States and World Affairs, 1931–1941

comprehensive student interactive giving the user a full scope of America's political and diplomatic responses to world events between the two world wars.

Having experienced the horrors of modern war during one world war, many Americans in the nineteen twenties concluded that there must not be another. A number of antiwar organizations had existed even before the war, but during the interwar period pacifism became the fastest-growing movement in America.

The United States may have refused to join the League of Nations, but this did not prevent numerous American politicians, businessmen, journalists, and activists from making proposals for multilateral agreements on arms control and collective security.

Through an examination of memoirs, photographs, and other primary source documents, students will examine the rise of antiwar sentiment in the United States, as well as some of the concrete measures taken during the 1920s to prevent the outbreak of future wars.

Guiding Questions

  • How did Americans' disillusionment with World War I help to shape U.S. foreign policy during the 1920s?

Learning Objectives

  • List the main reasons for the growth of antiwar sentiment after World War I.
  • Identify the U.S. foreign policy initiatives of the 1920s that aimed toward the prevention of war.
  • Assess the strengths and weaknesses of the Five-Power Treaty and the Kellogg-Briand Pact as means of preventing war.


It was not long after World War I ended that Americans started wondering whether their country's involvement in that conflict had not been a serious mistake. To many liberals, the Treaty of Versailles, which the Allies forced Germany to sign in June 1919, made a mockery of President Wilson's idealistic war aims. Instead of concluding a just settlement that would reform the international system and make future wars unlikely, the Allies, they concluded, had simply expanded their empires at the expense of their defeated foes. They began to question whether the loss of more than 120,000 dead, and nearly a quarter million wounded (not to mention the more than half a million Americans who died in 1918–1919 of Spanish Flu, which soldiers returning from Europe brought with them), was justified by this apparent return to "business as usual"?

It was once common for historians to refer to the 1920s as a period of "isolationism," thanks to the refusal of the U.S. Senate to ratify the Versailles Treaty, and the resulting failure of the United States to join the League of Nations. However, recent scholarship has focused on the ways in which, at both the public and private level, Americans remained committed to international efforts to prevent the outbreak of another war. U.S. bankers and businessmen, for example, with the active encouragement of the Harding and Coolidge administrations, concluded trade agreements with foreign firms, and extended loans on favorable terms to Germany in the belief that economic recovery was vital to the return of stability and the maintenance of peace.

But while the efforts of American businessmen to promote economic stability in Europe were no doubt important, the activities of various antiwar organizations were far more visible. In the wake of the horror produced by World War I, pacifism was the country's (indeed, the world's) fastest-growing political movement. Thousands of Americans—particularly women—flocked to organizations such as the National Council for the Prevention of War, and the Women's International League for Peace and Freedom. In the 1930s these groups would press for legislation that would keep the United States out of foreign wars; in the 1920s, however, the focus was still on international efforts to keep the peace—although without the sort of military commitments implied by the League of Nations.

Because most peace activists believed that the sheer size of the armed forces in the years leading up to World War I had been an important cause of the war's outbreak, one of the most consistent aims of the antiwar forces in the United States was the conclusion of arms control agreements. In this they were often able to make common cause with conservative Republicans who sought to decrease government spending of all types. It was this very alliance that resulted in the Washington Naval Conference of 1921–22, called to head off a naval arms race that seemed to be brewing among Great Britain, the United States, and Japan in the wake of World War I. In the resulting Five-Power Treaty the British, U.S., Japanese, French, and Italian delegations agreed to scrap—or at least to cancel construction of—significant numbers of capital ships (battleships, battlecruisers, and aircraft carriers), and to limit the overall tonnage of such ships in their navies to a ratio of 5:5:3:1.75:1.75. The U.S. Navy and its supporters were outraged, claiming that the country had lost its best opportunity to become the world's preeminent naval power, but such views were given scant regard in the face of the overwhelming demand for peace and economy in government.

Another important objective for the peace movement (both at home and abroad) in the 1920s was to have the waging of war declared a violation of international law. Few outside the community of antiwar organizations took this idea particularly seriously until 1927, when the French foreign minister, Aristide Briand, proposed a bilateral agreement with the United States in which both sides agreed never to go to war with one another. Frank B. Kellogg, the U.S. Secretary of State, suspected—rightly, it turned out—that this was a French attempt to lure the United States into an alliance against Germany, but he feared the political consequences of turning down such a seemingly innocuous proposal. He therefore offered to do Briand one better; why not, he suggested, make this a multilateral agreement in which all the world's countries would be invited to renounce war "as an instrument of national policy"? Thus the Kellogg–Briand Pact was born.

Most Americans embraced Kellogg-Briand as enthusiastically as they had welcomed the Five-Power Pact, and there was widespread support for the agreement even outside the peace movement. There were some dissenters, however. Some objected that, lacking any means of enforcement, the treaty was useless; others claimed that, because the treaty included exceptions for wars of self-defense, the signatories would simply attempt to argue that any war they decided to wage was being fought in the name of national self-preservation. In any case, such criticisms were quickly brushed aside, and the Senate ratified the Kellogg–Briand Pact by a vote of 85 to 1.

It is difficult to assess the long-term importance of either the Five-Power Treaty or the Kellogg-Briand Pact in contributing to international peace. However, it is clear that certain of the signatories felt free to ignore or even repudiate the agreements whenever they became inconvenient. Japan announced in 1934 that it would no longer abide by the naval disarmament clauses of the Five-Power Treaty. As for Kellogg-Briand, the promise to renounce war did not prevent Japan from invading Manchuria in 1931; nor did it stand in the way of repeated acts of aggression by Japan, Italy, and Germany later in the decade. What is clear is that the agreements demonstrated the enthusiasm of Americans for any measure that promised the prevention of war. Once the agreements fell apart in the 1930s, however, antiwar activists turned their attention away from international cooperation to preserve peace, and toward legislation that would keep the United States out of wars that might break out anywhere else in the world.

Preparation Instructions

  • Review the lesson plan. Locate and bookmark suggested materials and links from EDSITEment-reviewed websites used in this lesson. Download and print out selected documents and duplicate copies as necessary for student viewing.
  • Download the Text Document for this lesson, available here as a PDF. This file contains excerpted versions of the documents used in the various activities, as well as questions for students to answer. Print out and make an appropriate number of copies of the handouts you plan to use in class.
Accompanying Interactive

Go to the related interactive

Analyzing primary sources

If your students lack experience in dealing with primary sources, you might use one or more preliminary exercises to help them develop these skills. The Learning Page at the American Memory Project of the Library of Congress includes a set of such activities. Another useful resource is the Digital Classroom of the National Archives, which features a set of Document Analysis Worksheets. Finally, History Matters offers helpful pages on "Making Sense of Documentary Photography" and "Making Sense of Maps" which give helpful advice to teachers in getting their students to use such sources effectively.

Lesson Activities

Activity 1. Postwar Disillusionment

In the first activity students will learn about the disillusionment that set in after World War I, and which encouraged the spread of pacifism during the 1920s. Begin by introducing students to the concept of pacifism, defined as "the belief that disputes between nations can and should be settled peacefully." Lead a preliminary conversation with the class in which you ask the students whether, according to that definition, they believe themselves to be pacifists. Ask them under what circumstances they believe it is acceptable for the country to go to war.

Next hand out the following documents, reproduced on pages 1-3 of the Text Document that accompanies this lesson:

Note that the first reading mentions Wilson's 1918 Fourteen Points address, as well as certain provisions of the Treaty of Versailles. If these subjects have not been previously covered, students should be directed to the text of the Fourteen Points, which is available at the World War I Document Archive.

For homework have the students read the two documents, using the following questions to guide their reading:

  • In what sense did Fosdick regard the Treaty of Versailles as a betrayal of the principles that Americans fought for during World War I?
  • Why did Barnes believe that U.S. involvement in World War I was a "calamity"?
  • How, according to Barnes, would the war have turned out if the United States had remained neutral throughout?
  • Why does Barnes think that this "alternate ending" to World War I would have been preferable to what really happened?

After students have read the documents, ask them what how Americans felt about their country's involvement in World War I. With their input, create a list on the board of the reasons why U.S. intervention might have been bad for the United States.

Next, direct students to the following photographs and war memoirs. All of these are available via the EDSITEment-reviewed World War I Document Archive), but excerpts may be found on pages 4-6 of the Text Document.

Ask students to imagine that they are members of the National Council for the Prevention of War, one of the country's leading pacifist organizations during the 1920s. Students are to use the document excerpts above to create a political cartoon, either as homework or during class time, that will encourage people to embrace pacifism. If students need assistance on understanding political cartoons, direct them to the site "Analyzing a Thomas Nast Cartoon," part of the EDSITEment-reviewed resource History Matters.

Activity 2. The Quest for Peace

A determination to prevent the outbreak of future wars led Americans to embrace international treaties for the limitation of armaments and for the outlawry of war. In this activity students will consider two of the most famous agreements of the 1920s, the Five-Power Treaty of 1922 and the Kellogg-Briand Pact of 1928.

Divide the class into an even number of small groups. Assign half of the groups the following set of documents relating to the Five-Power Treaty signed at the Washington Naval Conference. These documents may be found in their entirety at the EDSITEment-reviewed resources Teaching American History and at WWII Resources, linked via the EDSITEment-reviewed resource Digital History). Excerpts are available on pages 7-11 of the Text Document.

Assign the remaining groups the following set of documents concerning the Kellogg-Briand Pact, available in their entirety at the EDSITEment-reviewed resources The Avalon Project and Teaching American History. Excerpts may be found on pages 13-17 of the text document.

Students are to pretend that they are presidential advisors who have been selected to review one these treaties to predict its potential effectiveness. Students are to individually read their documents, for homework or during class if time is available, and write a briefing to the president detailing their findings. A form has been provided for this briefing, on pages 12 and 18 of the Text Document.

Once students have completed their briefing papers, which might be used as a graded assignment, reassemble students into their groups to discuss their conclusions. Students should come up with a list of positive and negatives from their documents. To conclude, have a class discussion in which a master list of these positives and negatives is created. How effective do students think these measures would be in preventing the outbreak of future wars?


Teachers might wish to grade students on the political cartoons that they created for the first activity, and/or the briefing paper they completed for the second. Alternatively, students might be asked to write a 5–7 paragraph essay that directly addresses the lesson's guiding question: "How did Americans' disillusionment with World War I help to shape U.S. foreign policy during the 1920s?"

Finally, students might be asked to write a paragraph for each of the following, identifying and explaining their significance:

  • Pacifism
  • William E. Borah
  • Five-Power Treaty
  • Kellogg–Briand Pact

Extending The Lesson

The EDSITEment-reviewed site History Matters has a set of synopses of antiwar plays written during the 1930s. Teachers may wish to have groups of students write dialogue for some of these plays, and perform them in front of the class.

The EDSITEment lesson plan "Poetry of The Great War: 'From Darkness to Light'?" invites students to consider how the war was remembered through poetry. In particular, teachers might wish to have students read Wilfred Owen's powerful poem "Dulce et Decorum Est" and discuss what impact poems such as these might have had on the interwar peace movement.

Selected EDSITEment Websites

The Basics

Grade Level


Time Required

2-3 class periods

Subject Areas
  • History and Social Studies > U.S. > The Emergence of Modern America (1890-1930)
  • History and Social Studies > U.S. > The Great Depression and World War II (1929-1945)
  • Compare and contrast
  • Critical analysis
  • Critical thinking
  • Evaluating arguments
  • Historical analysis
  • Interpretation
  • Making inferences and drawing conclusions
  • Representing ideas and information orally, graphically and in writing
  • Textual analysis
  • Using primary sources
  • Writing skills
  • John Moser, Ashland University (Ashland, OH)
  • Lori Hahn, West Branch High School (Morrisdale, PA)


Activity Worksheets
Student Resources