When William Crosby was born on 19 September 1808, in Knox, Indiana, United States, his father, John Jeter Crosby, was 33 and his mother, Elizabeth Glenn Coleman, was 23. He married Sarah Jane Harmon on 4 March 1832, in Monroe, Mississippi, United States. They were the parents of at least 2 sons. William's father died in 1840. It is said that John Brown preached at John Jeter's funeral and then baptized Elizabeth, daughter of John Jeter and sister to William, on that same day. In 1844, John Brown marries Elizabeth and thus John Brown becomes the brother-in-law to William Crosby.
William traveled to Nauvoo in 1845 and was one of the militiamen that served as part of the Whistling and Whittling Brigade. He was one of the men that was asked to travel west with the John Brown Company (Mississippi Saints) in 1846. He leaves his family behind, as does John Brown, and is one of the seven men that return from Pueblo to his home in Mississippi in the fall of 1846. John Brown goes to Winter Quarters in 1847 and becomes part of the Brigham Young Vanguard company and arrives in the Salt Lake Valley on July 22, 1847. He returns back to Mississippi late in 1847. The Brown and Crosby families then migrate west in 1848 as part of the Willard Richards company. The William Crosby family that migrates west in 1848 includes William, his wife Sarah, mother Elizabeth Glenn Coleman Crosby, son Taylor, and 7 enslaved persons.
After immigrating to Utah in 1848, the Crosby family moves to Pine Valley, Washington, Utah in 1860 and Iron, Utah in 1870. In 1860, at the age of 52, his occupation is listed as farmer in Pine Valley, Washington, Utah. He died on 5 October 1880, in Kanab, Kane, Utah, United States, at the age of 72, and was buried in Kanab Pioneer Park Cemetery, Kanab, Kane, Utah.
(sources include: FamilySearch.org)