James Cahill, an art historian and curator who played an influential role in expanding the study and teaching of Chinese painting in the West before and after the opening up of U.S.-China relations in the early 1970s, died Feb. 14 at his home in Berkeley. He was 87.

The cause was complications of prostate cancer, said his daughter, Sarah Cahill.

A longtime professor at UC Berkeley, Cahill was a dominant scholar in his field for 50 years. In the late 1950s, he was one of a small number of Western scholars permitted access to the imperial paintings that had been evacuated to Taiwan before the Chinese mainland fell under Communist rule. He was allowed to photograph many of the works for "Chinese Painting," his classic 1960 text that for decades was required reading in Chinese art history classes.

He helped organize a seminal exhibit of Chinese imperial art from Taiwan's National Palace Museum that opened in 1961 at the National Gallery in Washington, D.C. Called "Chinese Art Treasures," the show traveled to other U.S. cities, including San Francisco, drawing large crowds to view works unseen in the West since the 1930s.

He also directed a project to produce high-quality color photographs of thousands of paintings from the National Palace Museum. The photographs became an invaluable resource for other scholars and museums

"He was a pioneer specialist in the field and had tremendous impact," said Rick Vinograd, the Christensen Fund Professor in Asian Art at Stanford University who studied under Cahill at Berkeley. "Early in his career, he was really a central figure in bringing knowledge of important monuments of Chinese painting to the general public and the academic world."

In 1973, Cahill was among the first group of American art historians to visit China after President Nixon's historic meeting with Mao Tse-tung in Beijing the previous year. They were granted extraordinary access to view and photograph rare paintings at the Palace Museum in Beijing.

Cahill, a spellbinding lecturer with an avuncular manner, often took controversial stands.

After the National Gallery exhibit, he argued at a symposium of Chinese art experts that notable Chinese painters during the Ming dynasty were influenced by Western art. His theory was denounced by some Chinese scholars but the notion of foreign influences in Chinese art of that period is widely accepted today.

In 1999, he caused a stir when he charged that "The Riverbank," a reputed 10th century masterpiece from the Southern Tang dynasty donated to the Metropolitan Museum of Art in New York, was a fake. He said the painting, attributed to the Chinese master Dong Yuan, was actually painted by a well-known forger, Chang Dai-chien, who died in 1983. The controversy was widely covered in art and mainstream publications.

The museum stood behind the painting, which remains in its collection, but Cahill never backed away from his judgment; in scholarly circles, the painting's authenticity is still a matter of debate.

"A lot of people felt his argument was quite convincing," said Adriana Proser, curator for traditional Asian art at the Asia Society in New York. "He was really quite an imposing figure because he had this brilliant memory and incredible bank of knowledge. It was amazing to hear him talk about painting."

Cahill did not grow up in a culturally privileged environment. He was born Aug. 13, 1926, in Ft. Bragg, Calif., and lived with a succession of relatives and friends after his parents divorced when he was 2. At Berkeley High School, he was interested in literature and music. His father, a swimming teacher at the YMCA, "was disappointed his son wasn't athletic," Sarah Cahill said in an interview.

He entered UC Berkeley in 1943 to study English but with World War II on, he decided to study Japanese instead. He was drafted into the Army and became interested in art while serving in Japan and Korea.

He returned to UC Berkeley in 1948 and earned a bachelor's degree in Oriental languages two years later. He then studied art history at the University of Michigan with Chinese art scholar Max Loehr, receiving a master's degree in 1952 and a doctorate in 1958.

He was curator of Chinese art at the Freer Gallery of Art in Washington, D.C., from 1958 to 1965, when he joined the UC Berkeley faculty. He taught there until his retirement in 1994.

He gave the Charles Eliot Norton lectures at Harvard University in 1978 and 1979; his talks were later published as a book, "The Compelling Image: Nature and Style in 17th Century Chinese Painting." In 2010, the Smithsonian Institution recognized his lifetime contributions to Asian art scholarship with the Charles Lang Freer Medal.

Twice divorced, Cahill is survived by two children from his first marriage, Sarah and Nicholas; two children from his second marriage, Benedict and Julian; and six grandchildren.

In his last years he kept up with technology, blogging on his website and recording a series of video lectures on Chinese landscape painting in collaboration with UC Berkeley's Institute of East Asian Studies.

In the weeks before his death, he made a farewell video for friends that reflected his well-known love of playful rhymes. The snowy-haired scholar recited a few lines by early 20th century humorist Clarence Day:

Tiddlely-widdley tootle-oo

All I want is to stay with you

But here I go. Goodbye.

elaine.woo@latimes.com