A growing number of people are devoting their attention to a closer study of foreign affairs. Many of them may not have the opportunity to read the larger volumes of histories; and, indeed, even if they had, they would find their choice of books very much restricted when they came to the more recent period of European and world history, although in the last year or so the gap has to some extent been filled up by several interesting studies of international politics in the nineteenth century. Some knowledge of this period is essential if we are to understand the full significance of the events of to-day, and if we are to form any helpful opinion of the course to be pursued in future. Historians often take for granted that their readers already have some general knowledge of the groundwork of events and they build up their structure of criticism, their delineation of policy and tendencies, and their survey of international problems on the assumption that the scaffolding has been erected. But often it has not, and then history, more especially the complex tangle of international history, becomes difficult to grasp. It may therefore serve some useful purpose if a few poles of scaffolding representing the dates and outline of conflicts and agreements between nations can be supplied in a very brief and easily intelligible form, a presentment of the bare record of facts which may be useful for reference. During the last hundred years war has been a more common occurrence in international intercourse than most people realize. The forty-two records of wars tabled in these pages do not cover the whole ground. They are the chief conflicts, or the conflicts fraught with the most serious consequences, but they are by no means the only occasions on which there was fighting in the world. Revolutions, unless they led to international war, are not mentioned, neither are expeditions such as the advance on Llassa, the Chitral expedition, the Indian frontier wars, the Kaffir wars, the Somaliland expeditions, the revolt of the Herreroes in German West Africa or the French expeditions in Morocco: the wars between the states of South America, with two exceptions, have also been omitted. But the list as it stands, is striking enough and may suffice to make the student inquire further into the circumstances which produced this almost unceasing strife.