By the time that Germany attacked France by marching through Belgium, Germany and France combined had amassed the largest armies ever seen on the face of the Earth and they had been in an arms race for several years. Each regarded the other as its natural enemy and a complicated series of alliances and treaties brought the rest of the world into a war that started in the Balkans but had its roots in fierce European Nationalism.
For a more detailed, (yet abbreviated), look at those causes I suggest [this link].
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World War I was the result of leaders' aggression towards other countries, which was supported by the rising nationalism of the European nations. Economic and imperial competition and fear of war prompted military alliances and an arms race, which further escalated the tension contributing to the outbreak of war........
...... Immediately following the assassination Germany pledged its full support (a blank check) to Austria-Hungary, pressuring them to declare war on Serbia, while France strengthened its backing of Russia. Convinced that the Serbian government had conspired against them, Austria-Hungary issued Serbia an unacceptable ultimatum, to which Serbia consented almost entirely.
Falling Dominoes
Unsatisfied, Austria-Hungary declared war on Serbia on July 28, 1914. On July 29, Russia ordered a partial mobilization only against Austria-Hungary in support of Serbia, which escalated into a general mobilization. The Germans threatened war on July 31 if the Russians did not demobilize. Upon being asked by Germany what it would do in the event of a Russo-German War, France responded that it would act in its own interests and mobilized. On August 1, Germany declared war on Russia, and two days later, on France. The German invasion of Belgium to attack France violated Belgium's official neutrality and prompted Britain to declare war on Germany. World War I had begun.
On September 14th, trench warfare began along the River Aisne in France, almost accidentally. A good account of it is [here].
For the uninitiated, trench warfare was where opposing armies dug fortifications separated from each other by a strip of open land, (no-mans land), and attempted to overrun the enemies positions by main strength and force of arms, a particularly costly form of warfare in terms of human lives. WW1 saw the end of set piece battles between opposing armies facing each other across a field of battle and the beginnings of modern warfare. The first machine guns, long range artillery, the first airplane battles, the first use of chemical weapons and the use of modern smokeless powders in rifle cartridges which increased the effective range and power of the rifle, the flame-thrower and grenades all saw first use in the killing fields of France. WW1 also saw the last of the mounted cavalry as an effective force on he battlefield.
(If you have questions about weapons or tactics, ask.)
To get an idea what life in the trenches was like [click here].
It has been estimated that 25,000 mi. (40,000 km) of trenches twisted across the landscape through Belgium, France and into Holland (enough to circle the world).
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Next, warfare and America enters the war.
Questions or discussion?
Warren
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