Resolved the Mosul Question by fixing the Turkey-Iraq border and granting Turkey a defined sphere of influence in northern Iraq.
Key Facts
- Date signed
- 5 June 1926
- Signatories
- Turkey, United Kingdom, Mandatory Iraq
- Primary dispute resolved
- Mosul Question (Turkey-Iraq border)
- Key region affected
- Mosul and Kirkuk region, northern Iraq
- Military provision
- Turkey granted right to intervene if border region destabilised
Location
Cause → Event → Consequence
Following World War I and the dissolution of the Ottoman Empire, the status of the Mosul vilayet remained contested between Turkey and British-controlled Mandatory Iraq. The League of Nations had awarded Mosul to Iraq in 1925, but a binding international agreement among the parties was still needed to settle the border dispute definitively.
On 5 June 1926 in Ankara, Turkey, the United Kingdom, and Mandatory Iraq signed the Treaty of Ankara. The agreement formally delimited the border between Turkey and Iraq, resolving the Mosul Question. It also included a clause granting Turkey the right to conduct military operations in the border region should it become destabilised.
The treaty confirmed British and Iraqi control over the Mosul and Kirkuk oil-rich region, ending Turkey's formal territorial claims there. Turkey nonetheless retained a recognised sphere of influence in northern Iraq beyond its modern boundaries, establishing a precedent for Turkish engagement in that area that would resonate in later regional politics.
Political Outcome
Turkey renounced claims to Mosul; the Turkey-Iraq border was fixed, with Turkey retaining a conditional right to military intervention in the border region.
Mosul Question unresolved; Turkey contested British-Iraqi control of the Mosul vilayet
Mosul and Kirkuk confirmed under British Mandatory Iraq; Turkey accepted border in exchange for sphere-of-influence clause