Jennetta, and their son left England in April 1841 and settled in Nauvoo,
Illinois, where Willard served as a land agent, a member of the city
council, and editor of the Times and Seasons. He also was appointed
the general clerk and recorder of various community organizations, including
the city council and the Nauvoo Temple. In December 1842 he was called
to be the LDS Church Historian and Recorder, a position he held until
1841 Joseph Smith asked Willard to be his private secretary. In this
capacity, he recorded much of the Mormon prophet's activities. He was
with Joseph Smith, Hyrum Smith, and John Taylor in Carthage jail when
Hyrum and Joseph were murdered. He supervised the removal of their bodies
and gave counsel to the church during that troubled time.
LDS Church historian, he was responsible for keeping the diary of Joseph
Smith and was greatly involved in the writing of the history of Joseph
Smith. He wrote a total of 1,884 pages of that history, which later
was edited by B.H. Roberts and published as the History of The Church
of Jesus Christ of Latter-day Saints.