Polish–British Common Defense Pact
E121104
The Polish–British Common Defense Pact was a 1939 mutual assistance treaty under which the United Kingdom pledged to come to Poland’s aid in the event of German aggression, forming a key diplomatic trigger for Britain’s entry into World War II.
All labels observed (7)
How this entity was disambiguated
This entity first appeared as the object of triple T1052421 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Polish–British Common Defense Pact Context triple: [1939 Defensive War, legalBasis, Polish–British Common Defense Pact]
-
A.
Poland–Soviet Union non-aggression pact
The Poland–Soviet Union non-aggression pact was a 1932 treaty in which the Second Polish Republic and the Soviet Union pledged to resolve disputes peacefully and refrain from military aggression against each other in the tense interwar period.
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B.
Sikorski–Mayski agreement
The Sikorski–Mayski agreement was a 1941 pact between the Polish government-in-exile and the Soviet Union that restored diplomatic relations and led to an "amnesty" for many Polish citizens imprisoned or deported in the USSR during World War II.
-
C.
Polish Round Table Agreement
The Polish Round Table Agreement was a landmark 1989 political accord between Poland’s communist government and opposition forces that initiated a peaceful transition from one-party rule to semi-free elections and ultimately to democracy.
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D.
German–Polish Non-Aggression Pact
The German–Polish Non-Aggression Pact was a 1934 treaty between Nazi Germany and Poland intended to guarantee mutual non-aggression, which was effectively nullified when Germany invaded Poland in 1939.
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E.
Polish–Romanian alliance
The Polish–Romanian alliance was an interwar military and political partnership between Poland and Romania aimed primarily at mutual defense against potential aggression from the Soviet Union and other regional threats.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Polish–British Common Defense Pact Target entity description: The Polish–British Common Defense Pact was a 1939 mutual assistance treaty under which the United Kingdom pledged to come to Poland’s aid in the event of German aggression, forming a key diplomatic trigger for Britain’s entry into World War II.
-
A.
Poland–Soviet Union non-aggression pact
The Poland–Soviet Union non-aggression pact was a 1932 treaty in which the Second Polish Republic and the Soviet Union pledged to resolve disputes peacefully and refrain from military aggression against each other in the tense interwar period.
-
B.
Sikorski–Mayski agreement
The Sikorski–Mayski agreement was a 1941 pact between the Polish government-in-exile and the Soviet Union that restored diplomatic relations and led to an "amnesty" for many Polish citizens imprisoned or deported in the USSR during World War II.
-
C.
Polish Round Table Agreement
The Polish Round Table Agreement was a landmark 1989 political accord between Poland’s communist government and opposition forces that initiated a peaceful transition from one-party rule to semi-free elections and ultimately to democracy.
-
D.
German–Polish Non-Aggression Pact
The German–Polish Non-Aggression Pact was a 1934 treaty between Nazi Germany and Poland intended to guarantee mutual non-aggression, which was effectively nullified when Germany invaded Poland in 1939.
-
E.
Polish–Romanian alliance
The Polish–Romanian alliance was an interwar military and political partnership between Poland and Romania aimed primarily at mutual defense against potential aggression from the Soviet Union and other regional threats.
- F. None of above. chosen
Statements (49)
| Predicate | Object |
|---|---|
| instanceOf |
bilateral treaty
ⓘ
defense pact ⓘ international agreement ⓘ mutual assistance treaty ⓘ |
| alsoKnownAs |
Polish–British Common Defense Pact
ⓘ
surface form:
Anglo–Polish Agreement
Polish–British Common Defense Pact ⓘ
surface form:
Anglo–Polish Common Defense Pact
|
| category |
Military alliances involving Poland
ⓘ
Military alliances involving the United Kingdom ⓘ Treaties concluded in 1939 ⓘ Treaties of Poland ⓘ Treaties of the United Kingdom ⓘ World War II diplomacy ⓘ |
| countrySignatory |
Poland
ⓘ
United Kingdom ⓘ |
| dateSigned | 1939-08-25 ⓘ |
| enteredIntoForce | 1939-08-25 ⓘ |
| geographicalScope | Europe ⓘ |
| historicalContext | prelude to World War II ⓘ |
| influenced | British foreign policy towards Eastern Europe in 1939 ⓘ |
| influencedBy | German occupation of Czechoslovakia in March 1939 ⓘ |
| language |
English
ⓘ
Polish ⓘ |
| legalBasisFor | United Kingdom’s entry into war with Germany in September 1939 ⓘ |
| legalNature | binding mutual defense commitment ⓘ |
| opposedBy | Nazi Germany ⓘ |
| partyObligation |
Poland obligated to assist United Kingdom in case of aggression by a European power
ⓘ
United Kingdom obligated to assist Poland in case of German aggression ⓘ |
| placeSigned |
London, England
ⓘ
surface form:
London
|
| politicalSignificance |
key diplomatic trigger for British entry into World War II
ⓘ
symbol of British commitment to Eastern European security in 1939 ⓘ |
| predecessor | temporary Anglo–Polish agreement of 1939-04-06 ⓘ |
| primaryAdversaryImplied | Nazi Germany ⓘ |
| purpose |
to deter German aggression against Poland
ⓘ
to formalize British security guarantees to Poland ⓘ to provide mutual assistance in case of aggression by a European power ⓘ |
| relatedAgreement |
Polish–British Common Defense Pact
self-linksurface differs
ⓘ
surface form:
Anglo–Polish military alliance
British guarantee to Poland of 31 March 1939 ⓘ Franco-Polish alliance ⓘ
surface form:
Franco–Polish alliance
|
| relatedEvent |
Invasion of Poland
ⓘ
surface form:
German invasion of Poland
outbreak of World War II in Europe ⓘ |
| resultedIn | British declaration of war on Germany on 1939-09-03 ⓘ |
| signatory |
Council of Ministers of Poland
ⓘ
surface form:
Government of the Republic of Poland
UK government ⓘ
surface form:
Government of the United Kingdom
|
| signedByRepresentative |
Józef Beck
ⓘ
Edward Wood, 1st Earl of Halifax ⓘ
surface form:
Lord Halifax
|
| terminationContext | superseded by wartime alliance arrangements after 1939 ⓘ |
| timePeriod | interwar period ⓘ |
| triggerCondition | aggression by a European power against either party ⓘ |
| yearSigned | 1939 ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Polish–British Common Defense Pact Description of subject: The Polish–British Common Defense Pact was a 1939 mutual assistance treaty under which the United Kingdom pledged to come to Poland’s aid in the event of German aggression, forming a key diplomatic trigger for Britain’s entry into World War II.
Referenced by (8)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Polish–British alliance
this entity surface form:
Anglo–Polish Agreement
this entity surface form:
Anglo–Polish Common Defense Pact
Polish–British Common Defense Pact
→
relatedAgreement
→
Polish–British Common Defense Pact
self-linksurface differs
ⓘ
this entity surface form:
Anglo–Polish military alliance
this entity surface form:
Anglo-Polish military alliance
United Kingdom declaration of war on Germany (1939)
→
legalBasis
→
Polish–British Common Defense Pact
ⓘ
this entity surface form:
Anglo-Polish military alliance
this entity surface form:
Anglo–Polish military alliance of 1939