On April 25, 1920, the Allied victors of World War I issued the San Remo agreement. It denied King Faysal’s bid for a sovereign Syrian Arab kingdom, dividing it into mandates to be governed by Britain and France. Surprisingly, politicians in the Kingdom’s capital of Damascus responded by convening a constitutional congress. They chose the leading scholar of Islamic reformism in the Arab world, Rashid Rida, as the congress president. Over the next two months, Faysal’s party debated constitutional articles with its opposition. Issues included the degree of bureaucratic centralization, women’s suffrage, and whether the head of state need be Muslim. The convention had not finished ratifying all articles, however, when the French overthrew Faysal’s regime on July 23, 1920. Existing scholarship on the Faysal era (1918-1920) does not adequately address the significance of the constitutional congress in Middle Eastern history. Using the original Arabic text of the constitution, Rida’s own writings, Arabic memoirs, and press accounts, this paper aims to recuperate the motives of those who convened the congress and to recapture the meaning of their debates. I hypothesize that the congress was a response to the logic of the League of Nations mandate, intended for peoples not yet ready for self-government. Politicians in Damascus sought to demonstrate their ability to establish a modern state, which in their eyes required a constitution. Second, I argue that the constitution was no window dressing. It is a historically significant document that captures political sentiment on the eve of French occupation. It was, most notably, the most democratic constitution to date in the Middle East, wherein the king’s power was significantly limited by the legislative branch. It also united secularists and Islamists around liberal principles. The only overtly Islamic element of the constitution was that the head of state must be Muslim. And yet, Rida pronounced it an Islamic form of government. Rida’s endorsement challenges the view that secular and Islamic politicians had divided into hostile camps before World War I. The political common ground between liberalism and Islamic reform, however, was sundered by France’s invasion. Rida and other Islamic leaders turned their backs on liberalism as a false universal model of justice, as a Trojan horse of European intervention, and as corrosive to local culture. Rida himself returned to Cairo and inspired calls for a new Arab caliphate and for explicitly Islamic politics like that of the Muslim Brotherhood.