Johnson's English forebears arrived in America in the mid-seventeenth century. Following the pattern of Western migration, his grandfather settled in Wisconsin in l842, and after the Civil War his father moved on to Iowa. When Johnson was fourteen years old, the family returned to Wisconsin, where he began formal schooling. He showed a great aptitude for drawing, and in 1891 went to Milwaukee, where he studied under various painters, and worked as an engraver and illustrater. In l895 he was in New York for a brief time, and studied at the Art Students League.
Johnson was in New York again in 1902. This time he pursued his artistic studies with Robert Henri at the New York School of Art, while working as a newspaper artist, engraving shop foreman, and later as a fashion artist. In 1904, after a successful exhibition of his western paintings, he went on an extended trip to Colorado where he gained first-hand knowledge of Western life, for use in his action-packed paintings. Returning to New York, he illustrated stories by Zane Grey and other writers, and continued exhibiting his paintings. In about 1927 he established his home in Alhambra, California, and there He developed an extensive collection of western hats, boots, saddles, ropes, and weapons which were useful props for his paintings as well as a personal extension of his fascination with the Western genre.
Johnson received the Salmagundi Club's Shaw prize in 1923, and the Allied Artists of America's Brown and Bigelow Silver Medal in 1929. In that same year he was elected to the National Arts Club, as well as to the Academy. Although easel paintings on Western themes were Johnson's primary work, he also worked occasionally on a larger scale; in 1927 in executed the curtain and two flanking murals on historical subjects for the stage of the Cathay Circle Theater in Los Angeles. A memorial exhibition of Johnson's work was held at Grand Central Art Galleries, New York in 1942.
At about the time Johnson became a member, the Academy instituted a biographical questionnaire form it asks all newly-elected members to complete for historical record. Johnson was unusually expansive in his, writing the following:
Born beside The Overland Trail on the prairie in South-Western Iowa, and having been reared in the Cattle Business, with its wild life in the open, it was but natural that I should choose the painting of Western Life as the means of expressing myself. As a boy I saw the long lines of Prairie Schooners and the Stage Coaches on the winding Overland Trail: the Long-horned Texas cattle and the cattlemen.
Since then I have been so busy exploring all parts of the West - associating with and living the life of the Mountain-man, Trapper, Cowboy, Prospector, and depicting on canvas the many phazes [sic] of Western Life which I have witnessed, and are now but a memory, that I haven't had time to visit Europe, but I hope to do so some day.
Although I am a legal resident of California, with a lovely home, spacious grounds, and a fine large studio, where many of my paintings are made, I spend at least three months every winter in my New York City home and studio.