John Gottlieb ErnestusHeckewelder (1743-1823) was an American missionary for the Moravian Church. Heckewelder studied the languages, manners, and customs of American Indians, particularly the Delawares. While a member of the American Philosophical Society, at Philadelphia, several of his contributions were published in their transactions. He also published Account of the History, Manners, and Customs of the Indian Nations who once inhabited Pennsylvania and the Neighboring States; Narrative of the Mission of the United Brethren among the Delawares and Mohegan Indians; and a collection of Names which the Lenni Lenape or Delaware Indians gave to Rivers, Streams, and Localities within the States of Pennsylvania. New Jersey, Maryland, and Virginia, with their Signification.