Rudolf Wunderlich, who died September 22 in California, was one of America’s leading dealers in Western art. The inheritor of one of New York’s oldest art galleries, he was considered a preeminent expert on Frederic Remington.

A skilled appraiser as well, Wunderlich’s services were in demand by the Autry National Center in Los Angeles; the Buffalo Bill Historical Center in Cody, Wyo.; the National Cowboy and Western Heritage Museum in Oklahoma City, and the Frederic Remington Museum in Ogdensburg, N.Y.

Wunderlich grew up in New York and went to work at his father’s firm, the Kennedy Galleries. Kennedy was founded on John Street in 1874 as H. Wunderlich & Company by Wunderlich’s grandfather, Herman. (During World War I, the name was changed to make it sound less German.) The gallery was James McNeill Whistler’s first American dealer, and legend had it that Whistler and Childe Hassam used to hang out there on Saturday nights.

In 1951, Wunderlich inherited the business. While the gallery dealt in all periods of American art, a specialization in Western art was already nascent. Wunderlich’s maternal grandfather had spent time on an Indian reservation with Sitting Bull in the 1880s, and his stories seem to have taken root in Wunderlich’s imagination, according to Wunderlich’s son, Gerold.

In the 1950s, Wunderlich worked closely with the pioneering Indian art collector and oil tycoon Tom Gilcrease, who eventually opened a large museum in Tulsa, Okla.

Wunderlich partnered in the 1960s with Lawrence Fleischman, who built up the gallery’s stock of American master originals, such as Copley, Hopper, and Ben Shahn, which continues to be the Kennedy Gallery’s focus.

Remington is popular with high-powered collectors like CEOs, and he is often forged. At one point Wunderlich estimated that there were 20 times as many forged copies of Remington’s “Bronco Buster” as there were originals. He was adept at spotting forger’s mistakes, such as omitting peculiarities in Remington’s signature (he used a Greek “e”). “There isn’t a collection in the country that doesn’t have at least one forgery, except the Remington Museum in Ogdensburg, N.Y.,” Wunderlich told Money magazine in 1986. He did not need to add that he was the one doing the authenticating.

Wunderlich advised many Remington collectors, including H. Ross Perot and John D. Rockefeller III. He also helped Jacqueline Kennedy to create the White House collection and aided in the selection of paintings for the American section of the Vatican Art Museum.

In 1983,Wunderlich sold out his part of the Kennedy Galleries partnership and moved to Chicago, where he bought a half interest in the Mongerson Wunderlich Galleries. (The partnership extended to marrying the gallery’s original owner, Susan Mongerson.) In Chicago, Wunderlich concentrated on the Americana he loved, including bronzes and American Indian art. Across the street from the main gallery was a smaller store selling Western wear, Indian blankets, and pottery.

In 1992, in partnership with art dealer Gerald Peters, Wunderlich purchased for $71,500 what was thought to be a minor Western landscape titled “Buffalo Hunt” by Hermann Herzog. The two were shocked when routine cleaning apparently revealed the signature of Albert Bierstadt, a far more esteemed artist. They sold the painting to David Rockefeller for $1 million. Rockefeller later claimed he had not been informed that there had ever been doubt about the painting’s authorship, and loudly demanded his money back. Peters and Wunderlich refunded the money but stuck by their attribution.

Wunderlich also had an extensive philatelic collection of proofs, which won prizes at international stamp shows. He liked to collect postal ephemera such as essays, designs for stamps that were never made, early artists’ sketches for stamps, and oddities like gunpowder-impregnated issues from the 19th century that were designed to self-destruct when canceled, inhibiting re-use.

Rudolf Wunderlich

Born November 13, 1920, at Tarrytown, N.Y.; died September 22 at Fountain Valley, Calif., of complications of Alzheimer’s disease; survived by his wife, Susan; sons Gerold, Theodore, and John; stepchildren Tyler Mongerson, Tina Smith, and Lindsey Mongerson, nine grandchildren and two great-grandchildren, and a sister, Roberta Chamberlain