Fourth Battle of Ypres
E429117
The Fourth Battle of Ypres was a World War I engagement in 1918, also known as the Battle of the Lys, in which German forces launched a major offensive against Allied positions in Flanders.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Fourth Battle of Ypres canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T4120639 — 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: Fourth Battle of Ypres Context triple: [Ypres, wasSiteOf, Fourth Battle of Ypres]
-
A.
Second Battle of Ypres
The Second Battle of Ypres was a major First World War engagement in 1915, notorious as the site of the first large-scale use of poison gas on the Western Front and heavy fighting involving Allied forces including Canadian troops.
-
B.
Battle of Loos
The Battle of Loos was a major British offensive on the Western Front in 1915 during World War I, marked by the first large-scale British use of poison gas and heavy casualties for limited territorial gains.
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C.
Battle of Neuve Chapelle
The Battle of Neuve Chapelle was a major early World War I offensive on the Western Front in March 1915, where British and Indian forces launched a concentrated attack against German positions in northern France.
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D.
Battle of Passchendaele
The Battle of Passchendaele was a brutal and muddy First World War offensive in 1917 near Ypres, Belgium, notorious for its massive casualties and minimal territorial gains.
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E.
Battle of Blanc Mont Ridge
The Battle of Blanc Mont Ridge was a major World War I offensive in October 1918 in Champagne, France, where American and French forces, including U.S. Marines, broke key German defensive positions and helped pave the way for the war’s end.
- 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: Fourth Battle of Ypres Target entity description: The Fourth Battle of Ypres was a World War I engagement in 1918, also known as the Battle of the Lys, in which German forces launched a major offensive against Allied positions in Flanders.
-
A.
Second Battle of Ypres
The Second Battle of Ypres was a major First World War engagement in 1915, notorious as the site of the first large-scale use of poison gas on the Western Front and heavy fighting involving Allied forces including Canadian troops.
-
B.
Battle of Loos
The Battle of Loos was a major British offensive on the Western Front in 1915 during World War I, marked by the first large-scale British use of poison gas and heavy casualties for limited territorial gains.
-
C.
Battle of Neuve Chapelle
The Battle of Neuve Chapelle was a major early World War I offensive on the Western Front in March 1915, where British and Indian forces launched a concentrated attack against German positions in northern France.
-
D.
Battle of Passchendaele
The Battle of Passchendaele was a brutal and muddy First World War offensive in 1917 near Ypres, Belgium, notorious for its massive casualties and minimal territorial gains.
-
E.
Battle of Blanc Mont Ridge
The Battle of Blanc Mont Ridge was a major World War I offensive in October 1918 in Champagne, France, where American and French forces, including U.S. Marines, broke key German defensive positions and helped pave the way for the war’s end.
- F. None of above. chosen
Statements (48)
| Predicate | Object |
|---|---|
| instanceOf |
World War I battle
ⓘ
battle ⓘ military offensive ⓘ |
| alsoKnownAs |
Battle of the Lys
NERFINISHED
ⓘ
German Spring Offensive in Flanders NERFINISHED ⓘ |
| belligerent |
British Empire
ⓘ
France ⓘ German Empire ⓘ Portugal NERFINISHED ⓘ United Kingdom NERFINISHED ⓘ |
| casualties | heavy on both sides ⓘ |
| commander |
Douglas Haig
NERFINISHED
ⓘ
Erich Ludendorff NERFINISHED ⓘ Ferdinand von Quast NERFINISHED ⓘ Henry Horne NERFINISHED ⓘ Herbert Plumer NERFINISHED ⓘ Horace Smith-Dorrien NERFINISHED ⓘ Rupprecht, Crown Prince of Bavaria NERFINISHED ⓘ |
| conflict | World War I ⓘ |
| dateEnd | 1918-04-29 ⓘ |
| dateStart | 1918-04-09 ⓘ |
| followedBy | Fifth Battle of Ypres NERFINISHED ⓘ |
| frontLength | approximately 20 miles ⓘ |
| involvedUnit |
British First Army
NERFINISHED
ⓘ
British Second Army NERFINISHED ⓘ German 4th Army NERFINISHED ⓘ German 6th Army NERFINISHED ⓘ Portuguese Expeditionary Corps NERFINISHED ⓘ |
| location |
Belgium
NERFINISHED
ⓘ
Flanders NERFINISHED ⓘ France ⓘ |
| notableEvent | collapse of Portuguese 2nd Division lines on 9 April 1918 ⓘ |
| objective |
to break Allied lines in Flanders
ⓘ
to capture Ypres and drive to the Channel ports ⓘ |
| operationName | Operation Georgette NERFINISHED ⓘ |
| opponent | Allied Powers NERFINISHED ⓘ |
| outcome | German offensive halted ⓘ |
| partOf |
German spring offensive of 1918
NERFINISHED
ⓘ
Hundred Days leading to the end of World War I NERFINISHED ⓘ |
| precededBy | Third Battle of Ypres NERFINISHED ⓘ |
| relatedTo |
Battle of Passchendaele
NERFINISHED
ⓘ
Spring Offensive of 1918 NERFINISHED ⓘ |
| result |
Allied strategic victory
ⓘ
German tactical gains ⓘ |
| strategicSignificance |
forced Allies to commit reserves to Flanders
ⓘ
threatened Allied control of Channel ports ⓘ |
| theatre | Western Front NERFINISHED ⓘ |
| year | 1918 ⓘ |
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: Fourth Battle of Ypres Description of subject: The Fourth Battle of Ypres was a World War I engagement in 1918, also known as the Battle of the Lys, in which German forces launched a major offensive against Allied positions in Flanders.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.