SAINT-SYMPHORIEN, Belgium - British Pvt. John Parr set off on his reconnaissance bike on the lookout for German troops amid the rolling farmland and woods south of Brussels in August 1914. It was the last anyone saw of 'Ole Man' Parr, the ironic nickname he won due to his tender age of 17. He became known as the first Commonwealth soldier to die on the Western Front of World War I, likely killed by German gunfire.
Another British private, George Ellison, was already moving to face the Germans in southern Belgium for the first battle of the two empires. He went on to survive the horrific slaughter of the Somme and Passchendaele and came back to the Belgian pastures, where he was shot and killed on Nov. 11, 1918 -- the last day of the war.
Now, Parr and Ellison lie separated by a few footsteps - and 9 million dead soldiers over four years - in the cemetery of Saint Symphorien. The jarring contrast of distance and death count symbolizes that, in the early August days of 1914, few knew what hell the great powers of the age unleashed when they declared war.
"They didn't, most of them, foresee what the war would turn into," said Oxford University historian Margaret MacMillan. "And if they had known what the war was going to be, four years of huge slaughter, consumption of resources, destruction in many cases of their own societies, they might have thought differently."
Nobody foresaw the cataclysm that would befall the world the day of Aug. 4 when the conflict erupted in full force with the German invasion of Belgium and the British declaration of war. Both sides believed the war would be over by Christmas. Instead, a battlefront scar would slowly and agonizingly rip across Europe, ravage whole societies and millions of families. It produced a moral wasteland in Germany that would become fertile ground for the rise of Nazism. Four empires would disappear.
On Sunday, French President Francois Hollande will host his German counterpart Joachim Gauck near their common border in oft-disputed Alsace to underline their friendship despite bitterly fighting two world wars in the 20th century. On Monday, Gauck will join Britain's Prince William, his wife Catherine and brother Prince Harry at the Saint Symphorien cemetery for a similar remembrance. In Britain, there will be ceremonies in Glasgow and a candlelit vigil at London's Westminster Abbey.
It will set off four years of centennial events from the United States to Russia, China to Australia, through Belgium, France, Germany and Britain -- underscoring that there was hardly a place on the planet untouched by the calamity.
With soaring tensions over Ukraine, the causes of World War I have had special resonance this year. A century ago few thought war was imminent until the June 28 killing in Sarajevo of Archduke Franz Ferdinand of the Austro-Hungarian empire.
Yet those shots fired by Serb nationalist Gavrilo Princip in Bosnia-Herzegovina carried tragic echoes. A political puzzle of complicated alliances fell into place that inexorably closed in on total war between the alliance of German and the Austro-Hungarian empires and the Allied powers of Britain, France and Russia.
Then as now, global peace and prosperity did not seem an unreasonable expectation.
"Europe went so quickly from peace to war -- five weeks, from the assassination June 28th in Sarajevo to a general war on Aug. 4," said MacMillan. "And you do feel, 'don't you realize what you will be throwing away.' People are on summer holidays in these lovely towns. Europe is getting more prosperous and they are about to throw themselves into this catastrophic struggle."
In a half dozen crises over the five years leading to the Great War, countries had always stepped back from the brink. This time though, "you had people who had decided for various reasons they were not going to back down."
Germany opened the Western Front on Aug. 4, sweeping into Belgium, hoping to overwhelm France before Russia had a chance to mobilize to the east.
The Schlieffen Plan was conceived as a lightning-fast operation that would bring German forces into Paris within weeks. It is why the fierce battles around Belgium's Liege and Mons have such significance -- since holding up the Germans for a few days, even in defeat, delayed their operation and deprived them of a swift victory.
It is what gives the death of Parr -- on Aug. 21, 1914 -- and some 1,500 British soldiers in Belgium military meaning, said Peter Francis of the Commonwealth War Graves Commission.
"It was an ordered defeat, if that makes sense," Francis said, "It is a defeat that bought time. It allowed the Schlieffen Plan to be held up and start to crumble. It was a defeat that bought another day."
Such defeats bought more than that. They bought another week, another month. And, in a sense, four more years.