Described as the "Father of the National Parks," Thomas Moran is widely recognized as being in the forefront of American landscape artists. He created the first paintings of the area that became Yellowstone National Park; these being instrumental, when shown to Congress in Washington, in obtaining the legislative support necessary to achieve that designation.

Moran's first work in Wyoming was in the Green River area in 1871, two years after the Union Pacific Railroad had been completed. A watercolor rendering of the cliffs near that railroad town bore his inscription, "First sketch made in the West." While on the same trip, Moran joined the Ferdinand Hayden expedition to the Yellowstone country, where he worked closely with photographer William H. Jackson to reveal the marvels of the area to the outside world. He sketched in the geyser basins and canyons, and at the waterfalls. The images gathered led to numerous oil paintings over the next 40 years, including "Grand Canyon of the Yellowstone," which hangs in the U.S. Capitol. Moran told a newspaper reporter that it was "the most wonderful region on the continent."

On subsequent visits to Wyoming, Moran produced "The Three Tetons," which is in the White House; and "Canyon of the Belle Fourche, Wyoming" in the collection of the Smithsonian's National Museum of American Art. His work is displayed in scores of the major museums in this country and abroad. In Wyoming, a mountain and a community bear Moran's name.

A souvenir pane of 20 subjects entitled "Four Centuries of American Art," issued on Aug. 27, 1998, in Santa Clara, Calif., included Moran's "Cliffs of the Green River, Wyoming." It was necessary to crop portions of the work at the right and left, so that the horizontally oriented painting would conform to the proportions of the 32-cent vertical stamp. The 80 million panes bore printing on the gummed side of each stamp describing the subject.

A University of Wyoming graduate in history, broadcasting executive Jack Rosenthal of Casper served as chairman of the U.S. Postal Service's Citizens' Stamp Advisory Committee in Washington, D.C.