One of the first Icelanders to join the Mormon faith was Gudmundur Gudmundsson. While studying as a goldsmith and watchmaking apprentice in Copenhagen Denmark, Gudmundur met with Mormon missionaries. While attending one of their meetings, Gudmundur listened to the words of Erastus Snow, then apostle of the Church of Jesus Christ of Latter-day Saints, believed his teachings, and was then baptized on February 15, 1851. He was given the priesthood calling of teacher by Erastus Snow, and was asked to return home to Iceland to teach others of the Mormon religion. Gudmundur wrote that few received the teachings of the Church of Jesus Christ of Latter-day Saints, and he was often mocked, spit upon, and persecuted by others.

Gudmundur spent three years sharing his faith with others in Iceland, but only baptizing nine others. He then returned to Denmark, where he spent eighteen months as a missionary on Sjaelland. Again, he encountered opposition and was arrested while preaching in Kalundborg. After seven weeks in prison, he was released, but was then forcefully drafted into the army and sent to Copenhagen. His experience in the services was one of further difficulty, as his weakened health made training hard and he was again subject to persecution and ridicule because of his beliefs. After one year, he was admitted into the hospital for illness, where he was able to find others who were eager to hear his message of the gospel. He was eventually released and discharged from service because of his illness, which had affected his lungs. Gudmundur then made the arduous journey to Utah, arriving in Salt Lake City on September 15, 1857.

With him on the journey were many friends and families who had joined the Mormon Church through Gudmundur's efforts. Among this group was Nels Garff, his wife Marie, an their children. Nels' strength did not last through the difficult trip and he died along the way. Honoring a promise made to him prior to his death, Gudmundur married Marie and together they had three more children. From this point, Gudmundur's life is not that of typical Mormon emigrants. He did not settle in Spanish Fork, instead, they travelled west to Sacramento, where they stayed for a number of years before returning again to Utah. The Gudmundsson family eventually settled in Lehi, Utah, where they purchased a home and Gudmundur set up a goldsmith and watchmaking business. Gudmundur died in 1883.