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During the summer of 1914, many people in Europe felt very optimistic about the future.
Mode technology was improving people's lives. Political freedom was gradually
increasing in many countries. New artistic styles and scientific discoveries were being
made. But later that summer, a terrible war began.  
In the early twentieth century, the various countries of Europe competed with each other
in an attempt to be the most powerful country on the continent. In each country, many of
the political leaders wanted to control more land, more people, and more resources.  
The First World War began when the archduke of Austria-Hungary was assassinated.
Austria-Hungary wanted to punish the assassin, who was from the small country of
Serbia. This led to a serious dispute, and soon other countries were involved. Within a
few weeks, a war had begun. On one side were Germany and Austria-Hungary, and on the
other side were Russia, France, and Britain.  
The people in these countries at first welcomed the news of a war. Many people were
 intensely patriotic, and supported the war effort without thinking carefully about the
reasons for the war. Some people thought that war would bring adventure and glory to
their lives, and they cheered enthusiastically in the streets.  
After the war started, it soon became clear that it was a terrible disaster. In the weste
part of Europe, the opposing sides fought many bloody battles. Soldiers on both sides
lived in filthy trenches that had been dug out of the ground. Sometimes, hundreds of
thousands of men were killed in battles that lasted only a few days. In most cases, these
battles did not result in large gains or losses of territory.  
The war continued for more than four years. When the war was finally over, millions of
people had been killed. Many people realized that their eageess to fight against other
countries had led them into a great disaster. This disaster did not end when the war
ended in 1918. During the next thirty years, there would be many violent revolutions in
Europe, and a second major war that would be even worse than the first.  
Today, people in most European countries no longer view other nations as enemies.
They have no interest in fighting wars with their neighbours. Instead, they are interested
in trading with the other countries, and in visiting those countries as tourists. The
lessons of the twentieth century have reminded people that wars can have terrible
consequences.