Why couldn't european countries maintain their overseas colonies after world war ii?

First of,the idea of having liberty and independence of their own ethnic race has spread to the colonies guring WWII,this caused the uprising of protests and unrest of colonies which shook the colonial rulers.

Also,after WWII,the European Nations were greatly damaged,as the war destryoed infrastructures and killed civilians,they faced the problems such as lack of labour,unemployment and hyperinflation. The nations were busy to settle the unrest and recovery within the nation and could not spare resources to maintain their colonies

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