After the defeat of the Ottoman Empire at the end of World War I, Britain and France divided an immense sweep of Southwest Asia (the Near East or the Middle East in European parlance) into two mandates, the spheres of influence that they coveted. The French were to administer Syria and Lebanon. The British were to administer Palestine, Trans-Jordan, and Iraq (again in European parlance).
In the first treaties after the war, the British were to administer the lower slope of Golan Heights as part of Palestine. In 1923, a comprehensive agreement, the last Treaty of Lausanne, included negotiations with the new Republic of Turkey. At this time, France and Britain adjusted the border by exchanging the Golan – to France – for a nearby region around Metula – to Mandated Palestine.
For sources see: National Geographic. 2008. Atlas of the Middle East, Second Edition (Washington, DC) p. 98. Also: Dan Smith. 2016. The Penguin State of the Middle East Atlas, Third Edition. New York: Penguin Books, p. 36-37.
The locals who lived on the Golan slope – who were not Jewish – were unhappy. Either they did not want to live under French administration or they didn’t see themselves as having much in common with Syria.
As has been typical, the Great Powers drew and have been drawing Middle Eastern borders without consulting the people most closely affected.
When Israel conquered the Golan Heights in 1967, remaining descendants of the post-World-War-I residents no longer had to live under Syrian rule.
Also in 1967, virtually the entire watershed of the Galilee was contained in one jurisdiction. When the State of Israel applied Israeli law to the Golan Heights in 1981, the entire region, on both sides of the upper Jordan River, was unified politically with defensible borders and one legal system.
In 1967, the Jordan Valley Unified Water Plan, originating in the 1950s, began to serve the primary stakeholders – Jordan and Israel. The Syrians and Lebanese had only been interfering by diverting water from both Israel and Jordan in violation of their agreements to the Water Plan.
In addition, Syria and Lebanon had not been interested in eradicating malaria from the Huleh Valley. Again, they were not stakeholders. I shouldn’t have to note that mosquitoes carrying malaria do not recognize political arrangements.
I do note that the Hasbani River rises in Lebanon and runs for 25 miles before it enters Israel. Lebanese stakeholders are partners in the Unified Water Plan, but the Arab League does not recognize this agreement and encourages mischievous violations within Lebanon.
Also of note: People who live in the Dara’a Governorate of southwestern Syria, as well as Jordanians, are stakeholders in the water resources of the lower reaches of the Jordan River. Syria’s Dara’a Governorate abuts the Golan Heights south of Syria’s Quneitra Governorate. The Quneitra Governorate lies partly in the disengagement zone between Syria and Israel along the plateau ridge of Israel’s upward slope of the Golan. Dara’a was an early site of conflict in the Syrian civil war, 2011.