Why did Thoreau write "Civil Disobedience"?

Henry David Thoreau wrote "Civil Disobedience" to protest slavery in the United States and the Mexican-American war. Thoreau was displeased with the government, and his essay helped to influence the Civil Rights Movement.

In the essay, Thoreau urged Americans to rebel if they were unhappy with the actions of the government. He instructed unhappy Americans to refuse to pay taxes since those taxes were in a sense, supporting the government's actions. Thoreau himself was imprisoned for refusing to pay taxes, but he believed that if he stayed true to his beliefs, he would always be free. He strongly believed that the government should continue progressing to reflect the citizens.