Truman Osborn Angell served many years as the official architect of The Church of Jesus Christ of Latter-day Saints (LDS Church) and was a member of the vanguard company of Mormon pioneers that entered the Salt Lake Valley on July 24, 1847. He designed the Salt Lake Temple, the Lion House, the Beehive House, the Utah Territorial Statehouse, the St. George Utah Temple, and other public buildings. Angell's modifications to the Salt Lake Tabernacle are credited with perfecting the acoustics for which the building is famous. Angell painted a bit as a nonprofessional, but rather able landscapist in his spare time.
In April 1856, Brigham Young asked Angell to leave his family and go to Europe so that he could learn the architectural designs there. After he returned from his mission to Europe, he continued to labor on the Salt Lake Temple.
In April 1856, Brigham Young asked Angell to leave his family and go to Europe so that he could learn the architectural designs there. After he returned from his mission to Europe, he continued to labor on the Salt Lake Temple. From 1861-1867 Angell had stepped down as Church Architect due to poor health and was replaced by William Folsom. However in April 1867 Angell was again sustained as church architect. Even during the time that he was not church architect, Angell worked closely with the construction of the Salt Lake Temple. He continued to serve as Church Architect until his death on October 16, 1887, at the age of 77. For more than thirty-five years he had worked on the Salt Lake Temple. It was said that he knew every stone in its walls. Of Truman O. Angell, Wendell Ashton wrote: "As long as the Salt Lake Temple stands, there will be a magnificent monument to the patience, skill and dedication of its architect." Although Angell did not live to see the temple completed, he was a key mover behind its being built.