In this thesis I have aimed to do three things. First, to show the principal ideas of Sir Norman Angell as they reveal themselves in his work. Second, to show the change and development of those ideas through the course of his life, and to see how they relate to changing circumstances. Third, to examine whether he influenced the course of British foreign policy, To do these three things I have first discussed his work in terms of related themes, and then I have considered these themes alongside the development of British foreign policy from approximately the turn of the century to the late 1950's. Whilst there has been interest shown in some aspects of Angell's writings by other scholars, my own work is the first attempt to bring together the whole of his writings in a comprehensive and systematic treatment. From first to last the extent of Sir Norman Angell's writing has been prodigious, amounting to over forty books and hundreds of articles. I hope that in attempting to distil his writing into a number of Significant themes I have managed to do justice to his purpose and preserved the perspective of his work. Naturally I have drawn upon material from wide and diverse sources, and I am accordingly indebted to a great number of people who have at some time provided me with information. Two persons should, however, receive especial mention. Sir Norman Angell has been most kind in allowing me to look through some of the more historical material, e.g. editions of War and Peace: A Norman Angell Monthly, and the work of the International Polity Summer School held in July, 1914, at his home in Haslemcre. The greater part of his books, documents and letters, have been given by him to the State Ball Teachers' College in Indiana. He has also been unsparing in the opportunities that he has given me to talk with him about his work and about British foreign policy. For his hospitality, encouragement, and other acts of kindness, I wish to thank him most sincerely. I am also indebted to Professor Martin Wight of Sussex University. His generous advice and guidance has encouraged me throughout my work. To him I wish to express my gratitude.