The Bari Incident: Chemical Weapons and World War II

Guiding Question:

Was the American plan regarding the use of chemical weapons in response to an Axis strike during World War II justified?


Students will utilize resources from the American Battle Monuments Commission including “How did Poison Gas Change Warfare?” and information on Sicily-Rome American Cemetery, as well as primary and secondary sources to examine the use of chemical warfare in World War II. They will review the use of gas in World War I, learn about the incident with the John Harvey at Bari, Italy, and complete a T-Chart illustrating pros and cons of using chemical weapons. Students will also ultimately take a personal stand on the issue in a culminating writing assessment, a letter with recommendations to President Franklin D. Roosevelt.


Historical Context

In 1943, the Allies’ focus was on the Mediterranean. Bari, Italy, a town of 200,000 on the Mediterranean Sea became an important shipping port, supplying British General Bernard Montgomery’s Eighth Army and American Major General Jimmy Doolittle’s Fifteenth Army. American President Franklin D. Roosevelt condemned the use of gas during World War II, but consistently promised that the U.S. would respond in kind if the Germans resorted to use of chemical weapons. On December 2, 1943, 30 Allied ships were crammed stern to bow into Bari Harbor when 105 Luftwaffe planes launched a crushing surprise attack. The U.S. Liberty ship John Harvey caught fire and exploded, sending her secret cargo of 2,000 bombs filled with deadly mustard gas spewing into the atmosphere.


At the conclusion of this lesson, students will be able to

  • Describe historical context and details of the Bari Incident;
  • Analyze the American chemical warfare policy; and
  • Synthesize sources to make a written recommendation to President Roosevelt on American policy and whether or not to continue manufacturing mustard gas.

Standards Connections

Connections to Common Core
CCSS.ELA-Literacy.RH.11-12.2 Determine the central ideas or information of a primary or secondary source; provide an accurate summary that makes clear the relationships among the key details and ideas.
CCSS.ELA-Literacy.RH.11-12.7 Integrate and evaluate multiple sources of information presented in diverse formats and media (e.g., visually, quantitatively, as well as in words) in order to address a question or solve a problem.
CCSS.ELA-Literacy.RH.11-12.9 Integrate information from diverse sources, both primary and secondary, into a coherent understanding of an idea or event, noting discrepancies among sources.

Connections to C3 Framework
D2.His.1.9-12. Evaluate how historical events and developments were shaped by unique circumstances of time and place as well as broader historical contexts.
D2.His.12.9-12. Use questions generated about multiple historical sources to pursue further inquiry and investigate additional sources.
D2.His.16.9-12. Integrate evidence from multiple relevant historical sources and interpretations into a reasoned argument about the past.
D 4.1.9-12. Construct arguments using precise and knowledgeable claims, with evidence from multiple sources, while acknowledging counterclaims and evidentiary weaknesses.


Activity One: Introduction to Chemical Warfare (15 minutes)

  • Activate prior knowledge on the use of gas in World War I by calling upon previous student knowledge and by using casualty information.
  • Ask the students: What do you remember about the use of poison gas during World War I?
  • Distribute a copy of the Geneva Protocol to each student to read.
    • Teacher Tip: When reviewing the Geneva Protocol, be sure to note that the U.S. did not sign until 1975. During World War II, Americans were not technically bound to these demands.
    • Ask students, Could this information be important when World War II rolls around? Why?

Activity Two: Chemical Warfare in World War II (45 minutes)

  • Show students the video clip, The Bari Explosion. This clip features the Wall of the Missing with members of the John Harvey highlighted. The clip briefly summarizes the events of December 2, 1943. Tell students they will now learn more about this tragedy and weigh the merits of the use of chemical weapons.
  • Divide students into groups of four to six students each.
  • Distribute one Document Packet to each group and one Pros and Cons of Chemical Warfare Chart to each student or group (at teacher discretion).
  • Ask students to generate a list of pros and cons for America's policy on chemical weapons.
  • Lead a class discussion, taking student input, and construct a list of all pros and cons the students generate on the board.
  • Tell students, I want you to think about all the sources you read today and make a personal decision. Imagine the front of the room is a scale or a continuum. The far left side will be for those students who think the production and use of chemical weapons in World War II was a good idea. The far right side will be for those students who think it is a terrible idea. You can be in between the two, if you are leaning one way or another. Please get up now and vote with your feet.
  • Call on students from either side and the middle to explain why they chose to stand where they did, asking them what pieces of evidence were most convincing.

Assessment Materials

Methods for Extension

  • Students with more interest in the role of the Chemical Warfare Service may research the role and responsibilities of members of this division.
  • Students can research more modern usage of chemical weapons in warfare and explore other historical or modern events where the Geneva Protocol has been called into question.
  • Students can investigate the use of Liberty Ships and the role of the Merchant Marine during World War II.


  • Teachers can adapt the project to younger students or English language learners by reducing the requirements for the culminating assessment.
  • The teacher may reduce the number of readings for activity two or annotate resources with helpful information to make them more easily digestible for younger students.


Return to Activity

Primary Sources

Other Sources