Jackson liked the cowboys he met there and developed an interest in the American frontier and Western genre starting at a young age.
In his early teens, he began taking Saturday classes at the Art Institute of Chicago after his teacher recognized his artistic abilities and secured a scholarship on his behalf.
[2][6] In 1942, when he was eighteen years old, Jackson enlisted in the Marines during World War II and became a sketch artist for the Fifth Amphibious Corps.
[2][7][8] In September 1944, Jackson returned to the United States and became the youngest ever Marine Corps combat artist at age twenty.
[6] During this "artistic conversion", Jackson moved to New York,[1][8] befriended Pollock, and began painting in the abstract expressionist style.
... John Wayne spoke for these people ... he was a wonderful embodiment of the timeless strength of the rugged individualist, the one-man majority I believe in with my entire being.
[8] In 1958, he was commissioned by Ambassador Robert Douglas Coe and the Buffalo Bill Center of the West's Whitney Gallery of Western Art, in Cody, to create the sequential paintings The Stampede (1965) and The Range Burial (1963), which were installed in 1965.
[8] In 1969, Jackson sculpted The Marshal for Time, which depicted Wayne as Rooster Cogburn in the film True Grit, riding a horse and carrying a rifle.
[2][3] Following Wayne's death in 1979, Jackson was commissioned by Great Western Savings & Loan to create a sculpture of Wayne, who had appeared in a series of commercials for the company during his last two years, for the Great Western Savings & Loan building (now Flynt Building) along Wilshire Boulevard in Beverly Hills, California.
[3] Prior to The Horseman's debut, the Beverly Hills Architectural Commission requested multiple changes, including the removal of multicolored paint and a motor in its base that would have slowly rotated the sculpture.
His bronze sculpture Sacajawea Modified II (2005) was the featured work for the 2006 Buffalo Bill Art Show and Sale, for which Jackson was named "Honored Artist".
[6] In 2007, California State University, Northridge opened the Washington Mutual Gallery in the campus' Redwood Hall, showcasing thirty Jackson sculptures on permanent display.
[22] His repertory included songs like "The Pot Wrassler" and "Streets of Laredo", and were "all sung in an authentic, unadorned style far removed from popular music or the folk-pop of the period".
[2][3] In addition to the brain injuries inflicted during his military service, he was allegedly diagnosed with narcissistic personality disorder and, according to his son, "treated everyday like a life and death battle".
[7] Matt continued efforts to fundraise the $5 million needed to maintain the collection and found an institution, and he also organized traveling exhibits to showcase his father's work.
"[8] The collection also included brushes, home videos, photographs, props, reference books, tools, Jackson's business and personal records, and more than 100 volumes of his journals.
[26] In 2015, Harry Jackson Studios exhibited Betio: Light and War, which consists of 56 paintings, for the first time and in conjunction with the Buffalo Bill Center of the West "Rendezvous Royale" fundraiser.
Artist and critic Gordon McConnell, who was a curator for the Yellowstone Art Museum, described the exhibit as a "monumental masterpiece" that "deserves a place among the important paintings of our time.
[8] In 2013, National Geographic contributor Jordan Carlton Schaul described Jackson as the "preeminent Western artist of his time" and "one of the most distinguished American sculptors and painters in history".
[25] Lyndon Johnson, Gerald Ford, and Ronald Reagan each appreciated and displayed Jackson's works, and selected his sculptures as gifts to heads of state.
[3][8] In 1976, Ford gave Queen Elizabeth II a sculpture called Two Champs,[31] which depicts Clayton Danks hanging onto Steamboat, the stallion from Bucking Horse and Rider seen on Wyoming's vehicle registration plates, to celebrate the United States Bicentennial.