Orson Pratt

Orson Pratt was one of the original Twelve Apostles, a prolific theologian, and the church’s foremost intellectual in the 19th century. A native of New York, Pratt joined the church in 1830 at age 19 after being taught by his brother Parley. He was a gifted mathematician and scientist who published extensively on Mormon theology.

Pratt’s relationship with church leadership was complicated. He was briefly excommunicated in 1842 after learning Joseph Smith had proposed marriage to his wife Sarah while Pratt was on a mission—though the excommunication was quickly reversed. His doctrinal writings sometimes clashed with Brigham Young’s views, leading to public disputes about points of theology.

He was a practicing polygamist with 10 wives. Pratt wrote the first systematic LDS theological works, including “The Kingdom of God” and mathematical calculations attempting to prove Mormon doctrines. He publicly announced the doctrine of plural marriage in 1852 and was among its most articulate defenders.

Despite occasional conflicts with Brigham Young, Pratt remained a faithful apostle until his death in 1881. His theological writings, while sometimes disavowed by later leaders, shaped early Mormon thought significantly.