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ABCD Encirclement

series of embargoes against Japan beginning in 1940

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionAug 19, 2026
Entity authorityQ5368015
Source-derived summary

The ABCD encirclement (ABCD包囲網, Ēbīshīdī hōimō) was a series of embargoes against the Empire of Japan by foreign nations, including the Americans, the British, the Chinese, and the Dutch. In 1940, in an effort to discourage Japanese militarism, these nations and others stopped selling iron ore, steel, and oil to Japan, denying it the raw materials needed to continue its activities in China and French Indochina. In Japan, the government and nationalists viewed these embargoes as acts of aggression; imported oil made up about 80% of domestic consumption, without which Japan's economy, let alone its military, would grind to a halt. The Japanese media, influenced by military propagandists, began to refer to the embargoes as the "ABCD ("American-British-Chinese-Dutch") encirclement" or "ABCD line".

Faced with the possibility of economic collapse and forced withdrawal from its recent conquests, the Japanese Imperial General Headquarters began planning for a war with the Western powers in April 1941. This culminated in the Japanese invasion of Malaya and Thailand, and the bombing of Pearl Harbor in December 1941.

Name

The name ABCD Line is of Japanese origin, having been disseminated by the Japanese government in propaganda and textbooks in the late 1930s. It is an example of Japanese propagandists portraying Japan as the protector of Asia, as in the name of the Japanese Empire's colonial holdings, the Greater East Asia Co-Prosperity Sphere. This wartime narrative portrayed Japan fighting against Western colonialists and Chinese communists primarily, overlooking the primacy of resource rich areas of Asia in Japan's annexing of lands. Japanese historian Saburō Ienaga writes that a key aspect of the Greater East Asian Co-Prosperity Sphere as propaganda was "liberating Asians from American and British imperialism".

Editorial summary

Begin with the source’s own compact description: “ABCD Encirclement” is series of embargoes against Japan beginning in 1940. The dossier treats that line as a proposition to test through ABCD, Encirclement and series, not as a finished interpretation.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1940, 1941—that can be checked directly. The linked authority record independently contributes the date 1930. For this dossier, ABCD, Encirclement and series is the immediate research focus.
Editorial analysis

Why this record matters

The phrase “series of embargoes against Japan beginning in 1940” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Aug 19, 2026. The linked authority identifier is Q5368015. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1940 and 1941.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “ABCD Encirclement”, its source revision and the description used here.
  2. Expand the search: follow ABCD Encirclement primary sources, ABCD Encirclement archive and ABCD research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “ABCD Encirclement”?
  2. What terminology or title could unlock a more precise catalogue search?
  3. Which cited source is closest to the event, object or claim?
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Source & attribution

This entry incorporates text from ABCD Encirclement” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.