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The Iran-Iraq Border: A Story of Too Many Treaties

By: Randall Lesaffer

On 22 September 1980, the armed forces of Iraq launched a massive attack against Iran. What Saddam Hussein (1937–2006) and his circle had expected to be a short war and a swift victory became an eight-years-long war of attrition that resulted in more than 1 million casualties and brought economic wreckage to both countries. Whereas the reasons for the war were complex, the Iraqi government sought the justification for its action partly in the age-old dispute over the Iran-Iraq border, claiming that Iran had illegally occupied some of its territory.

The border dispute between the two countries itself had deep roots. It predated the existence of the modern state of Iraq itself and went back to the conquest of Mesopotamia by the Ottoman Empire in 1514. From that time on, periods of conflict and compromise on the border issue alternated and were an endemic part of the overall relationship between the Ottoman and Persian empires, and between their successor states, in this case modern Iraq and Iran. From the mid-19th century onwards, several attempts were made to lay the border issue to rest once and for all through a comprehensive treaty settlement.

The oldest such attempt was the Second Treaty of Erzurum of 31 May 1847 (101 CTS 85). Before the 19th century, the territorial conflict between the Ottoman and Persian empires was not about the exact extent of their territories, but rather about the allegiance of the nomadic tribes roaming the areas at the margins of both empires. Between the major cities and fortifications of the two empires in the border area lay stretches of land where the control of one or the other empire was light and ill-defined, and which were the theatre of raids and low-intensity violence. The concept of a border as a strictly demarcated line which clearly defines the extent of the sovereignty and jurisdiction of the two neighbour powers is a European one. The demarcation of borders became a major concern of European polities from the late 17th century onwards. It was function to the rise of the modern, territorial State with its claim to exclusive jurisdiction over its territory.

The 1847 Treaty of Erzurum exemplifies the transplantation of the European model of territorial sovereignty to the Middle East on the wings of European imperialism. The treaty was the first serious attempt by the two leading powers of the Middle East to demarcate a precise border. The two powers acted under the pressure of the two European empires with the most significant interests in the region, Great Britain and Russia. These European powers not only sponsored the treaty but, as mediators, were directly involved in its negotiation and drafting. As much as it settled some outstanding disputes between the principal signatories, the Treaty of Erzurum primarily reflected the economic and imperial interests of London and Saint Petersburg, and their need to create a clear legal context for the agreements they had or desired with the Ottoman and Persian empires about their imperial and colonial rights.

Rather than settling the border disputes between the Ottoman and Persian empires once and for all, the Treaty of Erzurum outlined the dispute that would poison the relations between the two empires and their successor states for a century and a half. Whereas the treaty implicitly confirmed the sovereignty of the Ottoman Empire over the whole Shatt al-Arab, the river which is formed by the confluence of the Tigris and Euphrates and joins them to the Persian Gulf, in Article 2 the Ottoman sultan ceded some territories on the left bank of the river, between Khorramshahr and Abadan, to the shah of Persia. In the same article, the right of free navigation from the Persian Gulf to these points was guaranteed to the Persians. Hereby the treaty helped set the margins for the future conflicts over the status of the Shatt al-Arab, which forms modern Iraq’s major outlet to the sea, and adjacent lands.

Article 3 of the 1847 Treaty provided for a mixed commission to demarcate the borderline. Although the commission, to which Great Britain and Russia became party, set to work, it did so under the most inauspicious of circumstances. Before the closure of the treaty, the Ottoman government had obtained an explanatory note from Great Britain and Russia whereby the Ottoman concessions on the left bank of the river were given the most restrictive meaning (39 League of Nations Official Journal (1935), no. 2 , annex 1528, Appendix IIA, 191). At the exchange of ratifications in Istanbul in 1848, the Persian representative was made to accept this note, but the Persian government subsequently rejected it. Nevertheless, the demarcation commission set to work. By 1869, it had made some progress although a final agreement on the exact delineation of the border proved elusive. The whole episode of the commission’s activities illustrates that it had a higher priority to its British and Russian sponsors than to the powers concerned.

In the years just before World War I, the two European powers made a new attempt to push a final settlement on the border, and more particularly on the Shatt al-Arab. On 21 December 1911, a protocol additional to the 1847 Treaty was signed between the two empires at Tehran (215 CTS 138), whereby it was agreed to revive the mixed commission (Articles 1–3). The parties accepted that any claims the commission could not settle would be referred to the Permanent Court of Arbitration at The Hague (Article 4). The commission succeeded in reaching agreement on three quarters of the border. The compromise was laid down in the Protocol of Constantinople (Istanbul) of 17 November 1913 (39 League of Nations Official Journal (1935) no. 2, annex 1528, Appendix IIA, 201) Again, the agreement betrayed that the concerns of the European sponsors of the deal, in this case mainly Britain, dominated. In the 1913 Protocol, the Ottoman Empire ceded the whole anchorage at Khorramshahr, which was essential for the exploitation of the oil concession the British held from Iran, and which until after World War II would be the most important in the whole Persian Gulf area. The 1913 Protocol also provided for the continuation of the activities of the commission. While the commission had made great progress by 1914, the eruption of war impeded the ratification and implementation of its achievements.

After the foundation of the Kingdom of Iraq at the end of the war, Iran rejected the Treaty of 1847 and its additional protocols, invoking the invalidity of the 1847 explanatory note. In the mid-1930s, the conflict between the two states escalated to the point where they submitted it to the Council of the League of Nations. Although this did not lead to a direct result, the endeavours of the League helped to clear some misunderstandings and hurdles and facilitated the negotiation of a new treaty in 1937. The Treaty of Tehran of 4 July 1937 (190 LNTS 241) confirmed the previous treaties, but stipulated a new concession to Iran. Over a stretch of a few miles, between Khorramshahr and the great oil refinery at Abadan, the borderline between the two states was now fixed at the ‘thalweg’ – the line formed by the lowest points in the valley and the river – in the Shatt al-Arab, while for the rest of its course, the Shatt al-Arab remained fully under the sovereignty of Iraq.

After the rise to power of the Baath party in Iraq in 1968, the Iranian government decided to reject the 1937 agreement. This move formed part of the shah’s policy to destabilise the new regime in Iraq and exploit its tenacious hold on power. The Iranian policy was successful to the extent that in 1975, the Baath regime, the foreign and security strategy of which was increasingly controlled by then vice-president Saddam Hussein, decided to give in on Iranian demands regarding the Shatt al-Arab. In order to avoid war, and in exchange for an Iranian commitment to stop its support of the Kurdish rebellion against the Iraqi government, Baghdad agreed to cede half of the control over the Shatt al-Arab and fix the border over its whole course at the thalweg. This agreement, reached at Algiers on 6 March 1975, was subsequently confirmed in the Treaty of Baghdad of 13 June 1975 and its protocols (1017 UNTS 54). It was, among other goals, the humiliation of this agreement which Saddam Hussein wanted to erase from the pages of history with his invasion of 1980. On 17 September 1980, he openly abrogated the 1975 agreement, claiming that Iran had violated it by continuing to occupy some territories which the treaty had granted to Iraq and by resuming its support for the Kurds. By this abrogation, so the argument went, the border now returned to the one provided for by the 1847 agreement and subsequent agreements, implying that Iran at that time occupied even more Iraqi territory illegally.

With their acceptance of United Nations Security Council Resolution 598 (1987), first by Iraq and then in July 1988 by Iran, eight years into the war, the two belligerents agreed to settle their border disputes by peaceful means. The ongoing negotiations, which formed yet another new episode in a process which by then had lasted for a century and half, led to no result, until in August 1990, shortly after his invasion of Kuwait, Saddam Hussein threw in the towel and reconfirmed the border as it had been settled by the 1975 compromise, although he did so in the most circumspect of ways, leaving enough leeway for yet another future retraction. But for the time being, he conceded that his war for land had been fought for nothing.


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