The war by numbers - the staggering cost of the war
Ronan Abayawickrema breaks down the staggering cost of World War I in lives and resources
The estimated number of "boy soldier" volunteers under 19 – the legal minimum age for military service abroad – who lied about their age to join the British army during World War I.
The number of times German soldier and writer Ernst Jünger was wounded during World War I. Controversially, his book 'Storm of Steel', published in 1920, glorified the conflict, in contrast to the vast majority of World War I literature. He died in 1998, aged 102.
The minimum chest size, in inches, for a British army recruit in World War I.
The percentage of German men born in 1895 – and thus around 19 when World War I broke out – killed during the conflict.
The number of rounds fired by more than 1,000 German artillery pieces at the French lines at the start of the Verdun offensive in February 1916. The French held firm, despite horrific casualties on both sides.
The number of days Japan gave Germany to surrender its biggest overseas naval base, the Chinese port of Tsingtao, in an ultimatum delivered on August 15, 1914. When Germany did not reply, Japan declared war on August 23, and had captured Tsingtao – with British help – by November.
The approximate number of soldiers on all sides killed in World War I. Germany sustained the highest troop losses, at around 1.8 million; Britain's losses are estimated at 743,000 combatants, some 49,000 of whom were Irish.
The basic daily wage, in shillings, for a British army private in World War I.
The number of African soldiers from the colonies of French North Africa, now Algeria, and French West Africa, which included what is now Senegal and Mali, who died fighting for France in World War I.
One estimation of the total number of Irish servicemen who fought with the British army or navy during World War I.
The number of casualties sustained by the British army on July 1, the first day of the Somme offensive. Almost 20,000 of these soldiers were killed.
The number of people killed in German Zeppelin bombing raids on the docks at King's Lynn and Great Yarmouth on January 19, 1915. Fatalities due to air raids were tiny compared to those in World War II, but Germany's bombing campaign had a significant psychological effect.
The number of French divisions that refused to obey orders during the mutinies of April – June 1917. Order was only restored when General Robert Nivelle was replaced as French commander-in-chief by Gen Philippe Petain, who listened to the soldiers' grievances.
The number of "kills" attributed to German air ace Manfred von Richthofen, widely known as the Red Baron. Richthofen died when he was shot down in April 1918, either by rifle fire from the ground or by a Canadian pilot. His successor as commander of the Jagdgeschwader 1 squadron was a pilot named Hermann Goering.
The age of John Cornwell, a 'Boy, First Class' in the Royal Navy, when he fought at the Battle of Jutland in 1916. Cornwell, who had lied about his age to enlist, was awarded the Victoria Cross for continuing to man his gun on HMS Chester after the rest of the gun crew had been killed. He died of his injuries at hospital in England.
The time it took, in minutes, for the passenger liner RMS Lusitania to sink after being torpedoed by the German submarine U-20 off Queenstown, now Cobh, on May 7, 1915. The death toll of 1,195 included 123 Americans, provoking outrage in the US that contributed to America's eventual decision to join the war against Germany in 1917.
The weight of a World War I 'Tommy's' weekly ration of bacon. A soldier's daily calorie intake was around 4,600, compared with 3,400 calories a day for a worker on the home front.
The number of horses and mules deployed by the British army during World War I. To feed them, the army provided 2.9 million tonnes of oats and 2.4 million tonnes of hay as fodder over the four years of conflict.
See our dedicated World War 1 section here.
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