Born in Boston, Frank Fuller studied to be a physician, then a dentist, before taking work as a newspaperman. He campaigned for Abraham Lincoln, who in 1861 appointed him secretary of Utah Territory. He was soon the acting governor. Fuller met SLC in Virginia City in 1862, and the two maintained a lifelong correspondence. By 1865 Fuller had returned East, where until his death he speculated and engaged in a variety of businesses, including rubber goods, insurance and health food. In 1867 he acted as Mark Twain’s business agent.