On July 24 or July 25, 1846, Thoreau ran into the local tax collector , Sam Staples, who asked him to pay six years of delinquent poll taxes . Thoreau refused because of his opposition to the Mexican–American War and slavery , and he spent a night in jail because of this refusal. The next day Thoreau was freed when someone, likely to have been his aunt, paid the tax, against his wishes.  The experience had a strong impact on Thoreau. In January and February 1848, he delivered lectures on "The Rights and Duties of the Individual in relation to Government",  explaining his tax resistance at the Concord Lyceum . Bronson Alcott attended the lecture, writing in his journal on January 26:
“Civil Disobedience” is also important, however, because it has played an important role in Thoreau’s global influence. While Thoreau’s influence on Mohandas Karamchand Gandhi is exaggerated at times, it is clear that Thoreau’s essay and other writings provided Gandhi with a strategic advantage because of Thoreau’s place in American literature and because of Thoreau’s admiration for Hindu philosophy. Thoreau’s influence proceeded from Gandhi to Martin Luther King, Jr.; through his reading of Gandhi, King encountered Thoreau as a political ally for the struggle for liberation from segregation and racism. Today, Thoreau’s influence extends to environmentalism and struggles for human rights within the . and beyond.