This paper examines the roots of Egyptian-Iraqi rivalry in the context of the Second World War. This rivalry was one of the hallmarks of the post-war "Arab Cold War" as described in Malcolm Kerr's seminal work and it was most evident in the field of Arab unity. While most of the literature on the subject emphasizes the regional and anti-imperial considerations behind Egyptian-Iraqi competition for leadership of the Arab world, this paper focuses on the domestic and international pressures that drove this rivalry, with World War II serving as the catalyst. Both Mustafa al-Nahhas and Nuri al-Said, Prime Ministers of Egypt and Iraq respectively, found their nationalist credentials called into question due to their wartime cooperation with the British. Each hoped that claiming leadership of the larger Arab nationalist movement would provide a way for them to restore their prestige at home and deflect criticism of the domestic political situation. By the end of the war, the Arab unity movement took on new significance. Proponents of Arab unity viewed it as a way to ensure that the voice of the Arab states would be heard in post-war peace talks. By acting together, they might better represent their interests in light of the growing movement for the formation of regional and international organizations. Arab unity was not just a means of responding to the pressures of the western imperial powers, but also preparing for the emerging post-war reality of a world divided into American and Soviet spheres of influence, in which small states would be increasingly vulnerable. This paper explores the historical genesis of the "Arab Cold War" in both senses of the phrase by focusing on inter-Arab rivalries during the later war years as well as the role that Arab unity played in debates over the place of the Arab states in the emerging Cold War conflict. It examines the mechanics of Arab unity as conveyed in the proceedings of the meetings of Arab leaders held in 1944-1945 and the ways in which these ideas were presented to the wider public through the Egyptian and Iraqi Arabic mass media. It contributes to our understanding of the roots of the Egyptian-Iraqi rivalry for leadership of the Arab world not only in a regional and anti-colonial context, but also in a larger international one.