Certain historical events are remembered in terms of a single event which, in the course of minutes or hours, ushered in a new era. People who lived through Pearl Harbor could remember exactly where they were when they heard about the Japanese attack, a point when the course of US history (and world history) changed in the course of a couple hours.
Ninety-nine years ago, as the world plunged into the First World War, the experience was different. Rather than a single sharp event which plunged the world into cataclysm, there was a long series of events, at first not much noted, which in late July and early August of 1914 plunged all the major European powers into war over the course of a week.
There’s a certain tendency to look, with historical hindsight, at the assassination of Archduke Ferdinand on June 28, 1914 as an incident very likely to lead to world war. There were hints of such a possibility. German Chancellor Otto von Bismark famously observed in the late 19th century that the next great European war would start with “some damn fool thing in the Balkans”. When Archduke Ferdinant was assassinated, some people immediately worried that this would lead to a general war. (H. G. Wells was among those with the dubious honor of predicting a general war was coming after hearing news of the assassination on June 28th.) However, there had just been two full fledged wars in the Balkans during the last ten years, and neither had led to general war. Indeed, the great powers, for all their diplomatic entanglements, had been able to negotiate satisfactory (at least to themselves) peaces to both prior Balkan wars.