World War I (also known as the First World War, The Great War or the War to End all Wars) involved more than twenty sovereign nations over several fronts for more than four years of heavy fighting, with both sides employing tactics and technology that made the war unlike any before it. Nearly 10 million men died in the service of their countries' interests, economies crumbled, victors were given custody of land and people, and many of those who won, or suffered defeat, wound up playing different roles in the greater war to follow.
The war began after Archduke Franz Ferdinand, heir to the throne of the Austro-Hungarian empire, was assassinated by a revolutionary during a state visit to Serbia. Austria-Hungary, already interested in conquering Serbia, took this opportunity to declare war; this drew the hostility of Russia, who had guaranteed Serbia's independence. Germany was an ally of Austria-Hungary, and as the greater military power took the lead in what would be called the Central Powers, declaring war on Russia. Realizing that France posed the biggest threat due to its alliance with Russia, Germany launched an invasion through neutral Belgium, bypassing the heavily defended French-German border. However, since Belgium was guaranteed by the British, the Central powers now faced Britain's Royal Navy, the largest in the world at the time.
To the west, the Germans made swift progress early on, gaining a foothold in France, but both sides took great losses thanks to modern artillery, machine guns and rifles. The opposing armies dug in and the front line became largely static. In the east, however, the Allies had the upper hand thanks to Russia's sheer force of numbers overwhelming Austria. Germany shifted their attentions to the eastern front, quickly turning the tide in their favor, until the Russian revolution in 1917 led to Russia's surrender. In the west the Germans developed stormtrooper tactics to renew the offensive against a France suffering from large-scale desertions and war weariness. Germany's unrestricted u-boat warfare led to the USA's entry into the war, and Britain's naval blockade of German ports. Germany continued to defend its borders until the signing of the armistice in November 1918.
The fact that no large battles took place in Germany itself, and the censorship of the German press, led to a widespread belief among German citizens that their army had never been defeated, and politicians (and, among more conservative groups, Jewish financial institutions) were to blame for the loss of the war. The Dolchstosslegende (daggerstab legend), along with the harsh conditions imposed on Germany by the Allies, contributed to the rise of the Nazi Party.
World War I in Games
Entrenched in Places: A Meat Grinder Everywhere
As a game setting, World War I is a bit unconventional. The standard go-to for war, the infantry level shooter, doesn't have the same free-running combat scenario potential that the FPS favorite World War II had, because of the relative stagnation of the Western Front. There the Allied and Central powers fought at a standstill, largely relying on outmoded tactics that prevented significant gains, instead exhausting both sides through the loss of men and materiel who were stuck in fixed positions. Toward the end of the war these fronts finally changed, but as a setting for a game, there was little that could be heroic about catching a bullet while charging your opponent's trenches.
On the Eastern Front, between Central Powers on one side and Russia and allies on the other, there was greater motion, but Russia's own role in combat fell apart due to internal struggles which resulted in the revolution against the Czar.
The Southern Theaters, a loose association of several fronts that were mainly the Austro-Hungarian and Ottoman Empires' attempts to expand into sovereign states and the colonies and protectorates of the major powers, probably have the greatest potential for depiction in shooters as well as other genres, but they have largely been ignored for more accessible theaters and settings.
The New Tools of Destruction
The machine gun, used previously in the Crimea and other relatively minor conflicts, became a primary tool of the modern military, removing any pretense of the use of Napoleonic tactics (cavalry, fusillades, well-ordered, tightly packed lines of troops). Tanks, as well, saw use in World War I, but to a limited degree. Their tests in this war, though, were to set the stage for their much greater role in the Second World War three decades hence. Chemical weapons, including tear gas, mustard gas, and the highly lethal chlorine and phosgene, were used to devastating effect, largely as payloads for heavy artillery bombardment.
Arguably one of the greatest tools, though, was the use of quick deployment through ships, trains, and motor vehicles, sending hundreds of thousands of people, their weapons and their supplies, to points around the globe. It was probably this single increase in mobility that made the simmering tensions that had erupted between the various powers a world war and not an isolated conflict.
Mechanization at Sea
The Great War brought about huge advances in naval power, with huge ships bearing great, mobile cannons that could pound the shore, or other ships, from the safety of the sea. But the most famous sea-going weapon of this war was the submarine. It was to serve as a fierce weapon used to disrupt shipping and terrorize sea movement, as well as being used as propaganda against their users for their supposed dishonorable nature, despite Total War being a common doctrine at this time.
Anti-submarine weapons were quickly created to counter the threat, creating a compelling setting for submarine simulations.
The Freedom of the Air
One invention that developed rapidly and has been the focus of many games set in World War I is the airplane. Combat aircraft were not generally as well organized as they would be in later wars, but they served as scouts, interceptors and bombers. Propaganda on both sides emphasized pilots' chivalry, and lauded their countrymen's kills, publishing "Aces' " records to boost morale and support. The truth was often less noble, as is often the case in war, especially toward the end of the conflict. At the start few aircraft were heavily armed, many scouts having only a pistol to defend themselves, but after machine gun synchronization technology increased, the issue of heavy weapons chewing up your propellers ceased to be a problem, and deadly twin-mounted machine guns became a standard for many aircraft. These new, deadly systems could tear up the canvas and wood contraptions sending their pilots, often without parachutes, plummeting to their death, assuming they hadn't been cut to ribbons by the bullets themselves.
In addition, many games about aerial combat include sections where you shoot down lighter-than-air vehicles, namely airships and balloons. The latter were used as scouting platforms, where the volunteers would be suspended, usually protected by ground-based anti-aircraft cannons. Understandably, these were some of the first air vehicles to be equipped with parachutes for their human cargo. Zeppelins, mainly in the employ of Germany, were heavier craft with a greater lift capacity; these were often used as bombers because of this, protected by escort fighters and machine gun nests on the undercarriage. The well known problem with both of these conveyances was the hydrogen gas needed to keep them aloft (helium not being employed for this use until after the war was concluded). This highly flammable element could easily combine with oxygen if heated, forming water and giving off tremendous heat, spreading the reaction, causing a fiery explosion that would likely engulf its container. Taking full advantage of this, later fighter planes used incendiary ammunition, basically bullet grenades that exploded on impact, which they used to ignite the hydrogen and bring down the airships as quickly as possible.
The dynamics of the aerial combat, in stark contrast to the entrenched Western Front, along with the new machinery and the heavily publicized personalities of the various aces, make the air war arguably the most compelling and unique of the many situations of the war, and it's unsurprising that the vast majority of games set in World War I focus on the fight for aerial supremacy.