Iraq–Syria relations are the bilateral/diplomatic relations between the sovereign states of Iraq and Syria. Both nations are neighbours and they share the Iraq–Syria border. Relations are marked by long-shared cultural and political links, as well as former regional rivalry. The two countries took their present form after the Sykes–Picot Agreement to dismember the Ottoman Empire into British and French spheres of influence after World War I.
Iraq and Syria are united by historical, social, political, cultural and economic relations. The land known as Mesopotamia is Iraq and eastern Syria and is called such by its inhabitants. Both countries are largely Arab and Muslim, with Kurdish, Assyrians Chaldeans Syriacs, Arab Christians and Syrian Turkmen and Iraqi Turkmen minorities. Political relations between them have often been hostile. Ever since King Faisal took the Iraqi throne in the early 1920s, Iraqi leaders have dreamed of unifying the two countries. Relations were mostly poor during the Ba'athist regimes of Hafez al-Assad and Saddam Hussein, though Hafez's son Bashar al-Assad significantly improved relations. New diplomatic relations established in November 2006, were heralded as the beginning of an era of close cooperation between Iraq and Syria.
Both countries fought against the Islamic State of Iraq and the Levant (ISIL). In the Syrian Civil War, Iraqi volunteers have been fighting in Syria alongside the Syrian Army. The two countries are part of the Russia–Syria–Iran–Iraq coalition which was formed as a consequence of an agreement reached at the end of September 2015 between Russia, Iran, Iraq and Syria to "help and cooperate in collecting information about ISIL to combat the advances of the group, according to the statement issued by the Iraqi Joint Operations Command. From 2017 to 2019, Iraq joined the Syrian Civil War on behalf of the Syrian government and helped eliminate the Islamic State of Iraq and the Levant within the country.
Medieval period
In the ninth and tenth centuries, the Hamdanid emirate of Syria and Jazira broke off with the Abbasid Caliphate based in Iraq. The Hamdanids occupied parts of Abbasid Iraq in 942, before being expelled by the Buyids of Iran.
The Seljuks moved into Iraq and Syria during the eleventh century. Abbasid Iraq regained independence and the caliph was recognized as the spiritual leader of Sunni Islam by the Seljuks, including the Seljuks of Syria. In the 12th century, the Zengids took power in Syria and intervened in the war between Abbasid Iraq and the Seljuks. Saladin of the Ayyubid dynasty was later declared the Sultan of Egypt and Sultan of Syria; he aligned Syria to the Abbasids in Iraq.
Mandatory Iraq and Syria
In April 1920, the Allied San Remo Conference was held in Italy, which announced imposition of the British mandate over Iraq and the French over Syria. In June 1920, the Great Iraqi revolution, known as the Twentieth Revolution, broke out in an attempt to liberate Iraq from the British occupation, and on July 1920 the famous Battle of Maysalun took place, which ended with the French occupation of Damascus and the overthrow of King Faisal's Arab Kingdom of Syria.
The borders between the two countries were not defined in this early period in the history of the two countries, but the Ottoman border line between the Iraqi and Syrian states was the Khabur River, and therefore the cities of Al-Bukamal and Al-Mayadeen and Deir ez-Zor were Iraqi cities.
According to these borders, Britain, which was exercising legal sovereignty over Iraq at that period, sent political officers to rule these cities, but in late 1919 Syrian forces and clans launched an attack on these towns and captured British officers. As a result of this work, Britain recognized the fait accompli and the borders were amended to their current status.
From then until the end of World War II, the relations between the two countries did not witness any significant developments. Both countries were subject to the mandate regime, which prevents states from establishing political or diplomatic relations without the permission of the mandatory state. Therefore, relations between Iraq and Syria were limited to business relations.
The independence of Syria and Lebanon was declared in 1943 and 1946 respectively. Syria and Iraq established diplomatic relations on 8 November 1945 when has been accredited Charge d'Affaires of Iraq to Syria Ibrahim Fadli.
