Among the various challenges Yemen has to face, the fragmentation of its state throughout history and in its contemporary form, has deep implications. This second chapter examines how the contested legitimacy of the various Yemeni governments has shaped its international relations. A divided history has facilitated the domination of two actors: the United States on the one hand, Saudi Arabia on the other, which have both impeded in their own way on the capacity of the central state to monopolize power and violence. During the Cold War, in the frame of the unification process and then later during the so-called ‘Yemeni Spring’ and the war waged by the Arab coalition against the Huthi movement since 2015, such a division is an interesting, and yet often neglected variable, to understand the Middle East and international relations.