Eyjolfur was born 11 October 1829 at Illugastadir, Tjorn i Vatnsnesi, Vestur Hunavatn. His parents are Gudmundur Ketilsson, born 1791, died 24 June 1859; and Audbjorg Joelsdottir, born 26 January 1802, died 14 December 1884. Eyjolfur married Valgerdur Bjornsdottir 12 November 1853. Valgerdur was born 9 September 1828. Her parents are Bjorn Sveinsson, born 9 March 1795, died 25 November 1859; and Rosa Bjarnadottir, born in 1806.
Eyjolfur and Valgerdur had twelve children: Ogn Eyjolfsdottir 1854-1940, Eygerdur Eyjolfsdottir 1855-1885, Audrosa Eyjolfsdottir 1857-1941, Sigurbjort Eyjolfsdottir 1858-1859, Gudmunda Minnie Eyjolfsdottir 1859-1929, Bjarnlaug Eyjolfsdottir Anderson 1861-1942, Gudmundur Eyjolfsson Jameson 1862-1955, Frodi Eyjolfsson 1864-1864, Ketill Eyjolfsson (Kelly Jameson) 1865-1917, Numi Eyjolfsson 1867-1867, Eyjolfur Eyjolfsson 1870-1934 and Bjorn Eyjolfsson 1872-1884.
Eyjolfur was a farmer by trade, but he had other interests. He gathered eiderdown; he hunted and trapped gray foxes and seals and sold their hides. He was awarded a medal by the king of Denmark for improving the living standards of the people. This award is still in the little church near his old home in Eyjatbakki. He had his own personal seal or stamp, given him by the king of Denmark.
Eyjolfur and Valgerdur joined The Church of Jesus Christ of Latter-day Saints. The missionaries were Elders Haldor Jonsson and Einar Eiriksson. In 1883 Eyjolfur and Valgedur and eight of their children emigrated to Spanish Fork, Utah via North Dakota and Helena, Montana. Their son Bjorn drowned in quicksand near the Red River in Pembina, North Dakota in 1884.
Eyjolfur was an unusually intelligent and talented person. He helped many of the Icelandic people in Spanish Fork with medical problems. He was not licensed to practice medicine, so he was not accepted by the American Medical Association. He was a talented singer and wrote poetry in Iceland as well as in Utah. He was also a good wood carver and carpenter.
Eyjolfur and Valgerdur became disenchanted with the Mormon Church. They and all of their children, except Audrosa, left the Church and joined the local Lutheran congregation. Eyjolfur was a deeply religious person. He was kind and compassionate, and people who knew him loved and appreciated him. He was a student of the Bible and its teachings.
Eyjolfur died 19 September 1913 and is buried in the Spanish Fork City Cemetery. He went by Eyjolfur Jameson in Spanish Fork. He is number 125 in Icelanders of Utah.