Identify what you consider to be the three most significant political changes in the century preceding the start of World War I.

Identify what you consider to be the three most significant political changes in the century preceding the start of World War I. To support your choices, you will need to highlight a minimum two major Western nations and two colonies during this period. In addition to outlining the changes, your descriptions should include details related to economics and the rising political conflicts associated with imperialism, politics, and society.