جامعة ابردين2024-12-122024-12-12https://dspace.academy.edu.ly/handle/123456789/871how it could best be achieved was fully considered. Rules on treaties, diplomacy, travel, trade and more were discussed in a way that would best give rise to the peaceful coexistence between nations. Detailed legal rules with the purpose of guaranteeing the continuity of peace are suggested in his work. In contrast, Augustine, Gratian and Aquinas only engaged in limited discussions on some of the subjects of the law of war. Vitoria’s contribution on these matters was more extensive but even he lagged way behind A-Shaybani. The work of A-Shaybani was certainly as detailed, complex, comprehensive and useful as that of Grotius on international law. Besides the presentation and discussion of the merits of his work, a central purpose of this thesis is to argue that any future work on the history of international law that does not consider A-Shaybani’s contribution would be unsound.Abstract Mohammad A-Shaybani is one of the greatest scholars of Islamic international law (as-siyar). His book, As-Siyar Al-Kabier, is an eighth century textbook on international law. In this thesis I present and discuss the precise nature of A-Shaybani’s contribution compared to the other great contributions on international law made by Augustine, Gratian, Aquinas, Vitoria and Grotius. I affirm the view that A-Shaybani made a major contribution to the theory of international law that has been unacknowledged, and unjustly so, by scholarship.international law that does not consider A-Shaybani’s contribution would be unsound.