Jack Mormon

The term Jack Mormon is a slang term originating in nineteenth-century America. It was originally used to describe a person who was not a baptized member of the Church of Jesus Christ of Latter Day Saints but who was friendly to Church members and Mormonism, sympathized with them, and/or took an active interest in their belief system. Sometime in the early- to mid-twentieth century, however, the term began to refer to an individual deemed by adherents of The Church of Jesus Christ of Latter-day Saints (LDS Church) to be an inactive or lapsed member of the LDS Church who, despite his personal religious viewpoint, maintained good relations with and positive feelings toward the LDS Church.

The first publicly recorded use of the term was in 1846 by Thomas C. Sharp,editor of the Warsaw Signal, who referred to "A certain Jack-mormon of Hancock county..." Sharp also coined the term "Jack-Mason" to refer to those who were sympathetic toward Freemasons in the Anti-Masonic political movement. These sympathetic non-Mormons included Nauvoo Justice of the Peace Daniel H. Wells, who later joined the church, and soldier and diplomat Thomas L. Kane. Kane was identified as a sympathetic Jack Mormon by US Army officials and the media, some of whom asserted that he had been secretly baptised into the LDS faith. However friendly toward the LDS people, Kane remained a Presbyterian all of his life.

Several LDS historians believe that the term was used prior to Sharp's mention, and has ties to sympathetic Democrats in Jackson County, Missouri. Their belief is that the term originated in Missouri, during the Kirtland period of Latter Day Saint history, circa 1834. When Church members were expelled from Jackson County by a mob, many fled to Clay County, where local citizens, mostly Democrats, were sympathetic and friendly toward the Mormons. These citizens were pejoratively labeled "Jack" Mormons by the antagonistic citizens of Jackson County.

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