Thoreau spent a night in jail rather than pay for a war he opposed

Henry David Thoreau refused to pay a poll tax funding slavery and the Mexican-American War and spent a night in jail for it. He turned the experience into 'Civil Disobedience,' arguing that when a law forces you to be an agent of injustice, you have a duty to break it -- the essay later shaped Gandhi's and Martin Luther King Jr.'s resistance movements.

— Henry David Thoreau, Civil Disobedience (Resistance to Civil Government) — essay, 1849
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