Probably no period in the history of any country has been studied so thoroughly as the United States from the early national period to the end of the nineteenth century. Amidst the vast number of books and articles it is easy to lose sight of the source material on which they depend. This book examines the nature of the principal sources, the kind of information they yield and the limitations to their use. It is not a guide to specialised research, but a survey of the raw materials from which all history must be made. Nor is it a book about the philosophy or methodology of history; but from it emerges a very positive statement about the way in which history ought to be studied and written.