Traditionally, the murder of Austria-Hungary's crown prince Franz Ferdinand was the thing that started it all. Another important factor was the resulting invasion of Serbia by Austrian troops, which started a whole chain of other countries getting involved because of offensive/defensive mutual support-treaties that bound them. Russia got involved because it felt bound to support Serbia, Gemany was bound to support Austria-Hungary and Russia and France also had a mutual support treaty. Germany invaded France as a preventive strike since (watch closely!) France would have otherwise been bound to attack Germany when Germany attacked Russia in support of Austria which had attacked Serbia which had called in the support of Russia.
It is one of history's little ironies that the Serbian troops needed no-one's help as it turned out. They quickly kicked back the Austrian troops across the border and if everyone had just minded their own business, the Austrians and Serbians probably would have come to a quick face-saving agreement.
Many things, but one was Austro-Hungarian domination in the Balkans.
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Langston Hughes contributed to world war II by writing jinggles to incourage purchases of war bonds.
World War I changed the alliance system in Europe and had grave mental, economic, and political consequences for Germany that contributed to Hitler's rise to power.
Germany
the increased availability of credit.
The sinking of the Lusitania pushed the United States into the war.
world wide economic depression
After World War II with the sudden influx of men coming home after the war, a serious housing shortage started.
It was when A Slavic man Shot Archduke Ferdinand of Austria
The development of devastating new weapons technologies.
Many reasons contributed to the start of World War 1. These include the assassination if the archduke of Austria-Hungary Franz Ferdinand and his wife Sophie. Empires and alliances were another factor along with militarism, nationalism, and crises.
the diversity and lack of unity amoung the indian population
Many things, but one was Austro-Hungarian domination in the Balkans.
The United States emerged from World War II relatively unscathed. This made them the sole player pretty much in global markets. People had also bought a lot of war bonds, and invested in the country and in the war.Ê
One of them is the assassination of Franz Ferdinand.
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