It is well known that Marshall inserted a considerable segment on the history of economic thought in his Principles. In the first four editions this was prominently placed in Book I Chapter 4, following the two chapters on the growth of free industry and enterprise; only from the fifth edition did it take the more subordinate place of Appendix B. Apart from this major shift of Marshall’s sketch on the growth of economic science in the structure of the Principles, its contents themselves underwent relatively little change during the thirty years after 1890.1 Marshall’s objectives in this segment were not an attempt at history of doctrine but, by the inclusion of a view of the progress of the science, to instil into his readers an awareness of the relativity of economics and of the inevitable variations in human nature and institutions with which it was associated. The far more extensive ‘economic history’ which preceded the doctrinal history, it is also well known, was virulently attacked on its appearance by Marshall’s Cambridge colleague William Cunningham, and this exchange assisted subsequent views that Marshall’s work in no way can be described as that of a historian.2 His history of economics segment has, to my knowledge, never been directly discussed from the perspective of Marshall’s historical proclivities. The centenary commemorations of the publication of its first edition provide a good opportunity to do so and, more broadly, to examine quite generally, Marshall’s changing attitudes to the history of economics.3