Why did so many nations gain independence after World War I?

Explanation:

The aftermath of World War I saw drastic political, cultural, economic, and social change across Eurasia, Africa, and even in areas outside those that were directly involved. Four empires collapsed due to the war, old countries were abolished, new ones were formed, boundaries were redrawn, international organizations were established, and many new and old ideologies took a firm hold in people's minds. World War I also had the effect of bringing political transformation to most of the principal parties involved in the conflict, transforming them into electoral democracies by bringing near-universal suffrage for the first time in history, as in Germany (1919 German federal election), Great Britain (1918 United Kingdom general election), and Turkey (1923 Turkish general election).[citation needed]

it would be  

germany had to pay all damages related to the war.

and i think

germany had to take sole responsibility for the war.