The book was inspired by Thoreau's extended boating trip with his brother John; the first draft was completed while the author was living at Walden Pond. Unable to find a publisher, he subsidized its printing himself in 1849, leaving him in debt. "[I] have been ever since paying for it," he noted. Though these unsold copies represented his lack of literary success, Thoreau joked that it was more than symbolism: "They are something more substantial than fame, as my back knows, which has borne them up two flights of stairs." With both humor and indignation, the author also noted, "I have now a library of nearly nine hundred volumes, over seven hundred of which I wrote myself."
Thoreau's book is more than just an account of his geographical travels. He writes poetically, "we seemed to be embarked on the placid current of our dreams, floating from past to future as silently as one awakes to fresh morning or evening thoughts." Throughout A Week on the Concord and Merrimack Rivers, he muses about the world in which he lives, offers philosophical observations and, perhaps most often, his own questions about religion and mythology. In particular, he discusses not only the Christian God but also Greek gods, Hindu gods, the Buddha, and even Emanuel Swedenborg. "There are various, nay, incredible faiths," he writes, "Why should we be alarmed at any of them?" Further, he says:
The wisest man preaches no doctrines; he has no scheme; he sees no rafter, not even a cobweb, against the heavens. It is clear sky. If I ever see more clearly at one time than at another, the medium through which I see is clearer.