Henry David Thoreau’s classic book Walden; or, Life in the Woods (1854) helped establish the nature writing tradition in the United States and had a lasting impact on environmental thought. Influenced by transcendentalist ideas of self-reliance and spiritual communion with nature, Thoreau retreated to land owned by Ralph Waldo Emerson on Walden Pond from 1845 to 1847. “I went to the woods,” he wrote, “because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach.” A moderate success during Thoreau’s lifetime, Walden grew in influence after the author’s death as admirers began promoting his work.