Parley Parker Pratt Sr. (April 12, 1807 – May 13, 1857) was an early leader of the Latter Day Saint movement whose writings became a significant early nineteenth-century exposition of the Latter-Day Saint faith. Named in 1835 as one of the first members of the Quorum of the Twelve Apostles, Pratt was part of the Quorum's successful mission to Great Britain from 1839 to 1841. Pratt has been called "the Apostle Paul of Mormonism" for his promotion of distinctive Mormon doctrines.
Pratt explored and surveyed Parley's Canyon in Salt Lake City, Utah (named in his honor), and subsequently built and maintained the first road for public transportation in the canyon.
Pratt practiced plural marriage. He was murdered in 1857 by the estranged husband of his twelfth wife. Pratt fathered thirty children. His living descendants in 2011 were estimated to number 30,000 to 50,000. He is the great-great-grandfather of Mitt Romney, the 2012 Republican candidate for President of the United States, and Jon Huntsman Jr., diplomat and former Governor of Utah, who served as the U.S. Ambassador to Russia from 2017 to 2019.
