Answer :

There was many things in Europe that happened in both Wars. People dying, countries invading countries (Germany invading Poland). There was a lot of amount of mention between countries. Land issues, money issues! 
The Great Depression hit Germany extremely badly, people were starving and were homeless due to the banks closing in the USA. This lead to the rise of hitler and the nazis because he gave Germans a sign of hope for recovery and promised to make Germany great again. This lead to numerous invasions over Poland and Czechoslovakia and he re-militarised the Rhine land which scared France and Britain because they were worried about Germany invading them

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