We can see in all this a powerful motive for Austria to seek to gain possession of Servia, as a step towards possible future control of the whole Balkan peninsula. The commercial and manufacturing interests of Austria-Hungary were growing, and mastership of such a route to the Mediterranean would mean immense advantage to this ambitious empire. Possession of northern Italy once gave her the advantage of an important outlet to the Mediterranean. This, through events that will be spoken of in later chapters, was lost to her. She apparently then sought to reach it by a more direct and open road, that leading through Salonika. Such seem the reasons most likely to have been active in the Austrian assault upon Servia. The murder of an Austrian archduke by an insignificant assassin gave no sufficient warrant for the act. The whole movement of events indicates that Austria was not seeking retribution for a crime but seizing upon a pretext for a predetermined purpose and couching her demands upon Servia in terms which no self-respecting nation could accept without protest. Servia was to be put in a position from which she could not escape and every door of retreat against the arbitrament of war was closed against her. But in this retrospect we are dealing with Austria and Servia alone. What brought Germany, what brought France, what brought practically the whole of Europe into the struggle? What caused it to grow with startling suddenness from a minor into a major conflict, from a contest between a bulldog and a terrier into a battle between lions? What were the unseen and unnoted conditions that, within little more than a week’s time, induced all the leading nations of Europe to cast down the gage of battle and spring full-armed into the arena, bent upon a struggle which threatened to surpass any that the world had ever seen? Certainly no trifling causes were here involved. Only great and far-reaching causes could have brought about such a catastrophe. All Europe appeared to be sitting, unknowingly or knowingly, upon a powder barrel which only needed some inconsequent hand to apply the match. It seems incredible that the mere pulling of a trigger by a Servian student and the slaughter of an archduke in the Bosnian capital could in a month’s time have plunged all Europe into war. From small causes great events may rise. Certainly that with which we are here dealing strikingly illustrates this homely apothegm. HOW THE WAR BECAME CONTINENTAL We cannot hope to point out the varied causes which were at work in this vast event. Very possibly the leading ones are unknown to us. Yet some of the important ones are evident and may be made evident, and to these we must restrict ourselves.