Ralph Waldo Emerson was born in 1803 and died in 1882. Thus, he lived through a period of major social and political turmoil, perhaps more than any other time in American history. He witnessed the course of the Market Revolution, the rapid territorial expansion of the United States, and the rise of industry in the wake of the Civil War. But by far the most significant social and political turmoil in the nation during his life was related to slavery, the issue that tore the nation apart and led to the outbreak of the Civil War in 1861.

Like most Transcendentalists, Emerson was opposed to slavery on moral grounds, and he openly and publicly called for its abolition, writing bluntly that the nation must either "get rid of slavery, or . . . get rid of freedom." He openly supported fervent abolitionist John Brown even after his failed raid on Harpers Ferry, and he persistently called on Abraham Lincoln to bring about emancipation. Emerson vilified the South as corrupt and debased by the presence of slavery, and he predicted in the buildup to the Mexican War, widely seen as an effort to expand slaveholding territory, saying that "Mexico will poison us."

Emerson was also active in other reform movements that arose in response to conditions during the antebellum period. He called for full equality for women, for example, including the right to vote. Emerson was also at the center of social change during the period—his religious worldview was fundamental to the development of Unitarianism, a sect of Christianity that was in many ways a reaction to both the stodgy formalism of Congregationalism and the perceived anti-intellectualism of evangelicalism. His religious thinking, then, was an important offshoot of the Second Great Awakening.