Long ago, a big fight began. 

A big fight began in a land called Poland. 

In 1939, a large war began in Europe. 
Germany and the Soviet Union had made a secret deal. This was called the Molotov–Ribbentrop Pact. 
Germany attacked from the north, south, and west. The Soviet Union attacked from the east on September 17. This second attack made it very hard for Poland to defend itself.
France and the United Kingdom had deals to help Poland. They declared war on Germany on September 3. However, their help for Poland was very small.
Polish soldiers fought hard to protect their land. 
This event ended the Second Polish Republic. Many Polish people joined groups to fight back from underground. Others left to join the Polish army in other lands. 
The invasion of Poland was a major event that began World War II. 

The fighting happened in several stages across the country. Germany and its allies attacked from the north, south, and west. 

Before the war, tensions grew between Germany and Poland. 

Specific dates show how quickly the situation changed for Poland. The German invasion began on September 1, 1939. 
Even though the country was taken, the story did not end there. 
The invasion of Poland was a massive military campaign that began World War II. 
The invasion followed years of rising tensions and aggressive diplomacy. 
Before the fighting started, Germany and the Soviet Union made a secret agreement. 
The military campaign unfolded in several rapid and difficult stages. 

The situation became impossible for Poland when a second front opened. 
The invasion resulted in the total collapse of the Second Polish Republic. Following the defeat, Germany annexed western Poland and the former Free City of Danzig. The remaining territory was placed under the administration of the General Government. The Soviet Union incorporated its new lands into the Byelorussian and Ukrainian republics. They immediately began a process of Sovietization in these areas. This reorganization changed the political map of Europe for the duration of the war.
Despite the military defeat, the Polish people did not stop fighting. 
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