The war has an important role in the historical process in England, with direct influence to the theoretical thought produced in her academy. The focus of this article is the issue of war in the "English School of International Relations", through the analyses of Carr, Butterfield, Wight and Bull's works. The article concludes that Carr was an outsider of the English school of International Relations. Nevertheless, his critics against the international harmony of interests and his call to the building of a new international moral made possible further research developments on international society. Butterfield, Wight and Bull are rationalist in their views on war. This tradition is a product of disenchantment with dialectical and antithetical explanations in International Relations: realism x idealism. Against this background, the war is, first, a permanent element of the International Relations, whose most important objective is provide order and not to keep the peace. Second, the war is, on one hand, an instrument of power politics and, on the other, a threat to be contained. In these analyses there is sophistication, both in substance and in methodology, among the thought of Butterfield to Wight, and of Wight to Bull.
War; English School of International Relations; International Society