Edgar Allan Poe's tale “The Tell-Tale Heart” was first published in the premiere issue of the Pioneer, an ambitious and short-lived literary journal edited by James Russell Lowell and Robert Carter. In 2013, a previously unpublished letter from Poe to Lowell, dated November 24, 1842, was auctioned at Christie's and is now in private hands. This letter contains Poe's offer of the tale to Lowell and his first mention of its title to the editor that went on to publish it. This article, based on direct examination of the letter, provides its full text, along with a contextual discussion of the Pioneer's brief existence and an exploration of the relationship between Poe and Lowell from their first correspondence in 1842 to their falling out and mutual criticism in the late 1840s. The newly discovered letter gives us a more complete picture of the publication of one of Poe's best-known tales and of the relationship between two major figures of nineteenth-century American literature.