This week marks 90 years since the end of World War I, surely the last major anniversary for its handful of ageing veterans as what was dubbed the "War to End All Wars" slips from living memory into history.
In reality, rather than mark an end to human conflict, the Great War merely set the tone for the 20th century's litany of brutality, although in terms of sheer mass killing on the battlefield it has rarely been equalled since.
Many conflicts followed but November 11 -- the eleventh hour of the eleventh day of the eleventh month, when the World War I armistice was signed -- has become the moment when the world remembers the dead from all of them.
Tuesday's ceremonies will be solemn but in some countries a little less personal, as the last of the combat veterans from World War I pass on.
Erich Kastner, the last of the German troops, died on January 1 this year, aged 107. The last French veteran, Italian-born legionnaire Lazare Ponticelli, survived him by only two months, dying on March 12 aged 110.
Since the two faced each other across the Western Front -- indeed, since France and Germany fought each other again in World War II -- their countries have become allies at the heart of a united Europe.
But, as France's minister for veterans' affairs Jean-Marie Bockel said last week: "Reconciliation is not forgetting. To forget would be the worst thing."
"Now that the last veteran has gone, 90 years on we once more share a moment of awareness. This war is part of our collective memory, and he who does not know his past has no future," he said, inaugurating a memorial.
There are three surviving members of the British forces that joined France, Russia and Italy in the battle against Germany and the other Central Powers.
Henry Allingham is the oldest, having turned 112 in June. As a naval air service mechanic he served in the 1916 Battle of Jutland in the North Sea, before joining the new Royal Flying Corp at the Somme.
Two years his junior, Harry Patch fought in the trenches opposite the Belgian town of Ypres in the Duke of Cornwall's Light Infantry, and the Royal Navy's 107-year-old Claude Choules served on board HMS Revenge.
In 1917, after three years of bloody conflict, the United States entered the war with Britain and France, and brought with them ambulance driver Frank Buckles, now 107 and living in West Virginia.
On Tuesday, France's President Nicolas Sarkozy, Britain's Prince Charles, the speaker of the German parliament Peter Muller and Australia's Governor General Quentin Bryce will hold a solemn ceremony of remembrance.
They will meet at Fort Douaumont, epicentre of the 1916 Battle of Verdun, for speeches and prayers at the ossuary where lie the remains of 300,000 men cut down by machine-gun and artillery fire in 300 days and nights of hell.
Afterwards, Sarkozy will visit the nearby German cemetery.
In August 1914, many of the fresh-faced young volunteers who marched out of towns over much of Europe were confident, little suspecting what mayhem modern industrial weaponry would wreak on the battlefield.
By Christmas, hundreds of thousands were dead, and fatality rates in the tens of thousands on a single day had already become commonplace.
Guns had become highly efficient, and railways could bring fresh troops and equipment up to the killing fields as fast as they were destroyed.
Despite these apparent advances, the war in the west rapidly became a horrific stalemate, set in a sea of mud, barbed wire and rat-infested trenches.
Fighting on the Eastern Front, in the wide open spaces of Russia and Poland, was more mobile, but there too many battles caused astronomic casualties. There was also major combat at sea, and in the Middle East.
In all, the First World War killed some 10 million military men and left 20 million injured, many of them disfigured by explosives or poison gas, or reduced to human wrecks by what became known as "shell shock."
Among the major belligerents, Germany lost 1.9 million, Russia 1.7 million, France 1.4 million, the Austro-Hungarian empire a million and Britain 760,000.