As the scion of a shipping empire, William Matson Roth grew up in a 43-room home with 16 acres of formal gardens. When his twin sisters made their debut at a ball there in 1939, The San Francisco Chronicle said they were “launched like luxury liners.”
But Mr. Roth did not relax in luxury. In a long lifetime of public service, he served as a regent of the University of California for 16 years; sparred with the state’s governor, Ronald Reagan; briefly ran for governor himself; preserved historic Ghirardelli Square in San Francisco, his hometown; and, with far-reaching impact, was the chief negotiator for the United States in a groundbreaking international trade agreement in 1967.
He died May 29 at a hospital in Petaluma, Calif., where he lived. He was 97.
Mr. Roth was the American point man in “the Kennedy round” of negotiations over reducing international tariffs. Authorized by President John F. Kennedy, they began in 1964, at the Palace of Nations in Geneva, Switzerland. Mr. Roth joined the effort in 1965, appointed by Lyndon B. Johnson, Kennedy’s successor.
In the end, after three years of byzantine and often bitter haggling and bartering, the United States and 65 other nations agreed to reduce most tariffs by more than a third.
“Far more than any other American, including President Johnson, William Roth is responsible for the result, for better or worse,” The New York Times said in a profile of him.
Mr. Roth had several times threatened to walk out rather than accept an unbalanced deal. “You can’t play poker unless you’re willing to pull out your chips,” he told The Times.
The final agreement, signed on June 30, 1967, included the most comprehensive reduction in tariffs since Western nations began a series of trade-liberalization negotiations after World War II. The terms included an unprecedented anti-dumping provision, barring manufacturers from exporting products at below home-market prices or below production costs, and an easing of trade terms for developing nations.
Historians have seen the pact as representing the dawn of an era of ever-freer international trade.
It was a business Mr. Roth had been steeped in practically since birth.
William Matson Roth was born in San Francisco on Sept. 3, 1916, a year before his grandfather Captain William Matson died at 67. The captain, who came from Sweden as an orphaned teenager, began a long association with Hawaii in 1882 by sailing his three-mast sailing ship to Hilo from San Francisco.
The shipping line he founded, the Matson Navigation Company, started some of the first regular tourist cruises to the islands and pioneered nautical innovations like cold storage and electric lights. Captain Matson built hotels there, including the Royal Hawaiian.
Mr. Roth’s father, William P. Roth, succeeded Captain Matson as company president. By the 1950s, the younger Mr. Roth was also a top company executive and helped introduce containerization to the industry.
Mr. Roth attended the Cate boarding school in Carpinteria, Calif., and Yale, where he studied English and history and graduated in 1939.
Pursuing his passion for literature, Mr. Roth, in 1941, joined with Jane Grabhorn, a noted printer, typographer and bookbinder in San Francisco, to start Colt Press, which brought an Art Nouveau sensibility to publishing finely crafted literary books by authors like Jane Austen. During World War II, he served with the Office of War Information in a psychological warfare unit in Burma.
From 1951 to 1960 he was a director and officer of Matson Navigation, and for the next three years he was chairman of the Pacific National Life Assurance Company.
President Kennedy appointed him deputy to Christian A. Herter, the president’s special trade representative, in September 1963. When Mr. Herter, a former secretary of state in the Eisenhower administration, had heart surgery in 1965, Mr. Roth became the chief trade policy maker and succeeded him after Mr. Herter’s death in December 1966.
Even while wrestling with thorny trade issues, Mr. Roth remained active as a regent of the University of California. He spoke in support of students demonstrating for “free speech” and against the Vietnam War. Edwin W. Pauley, an outspoken conservative regent, denounced Mr. Roth as “ultra-liberal.”
Mr. Roth stayed on after Reagan became governor in 1967 and appointed conservative regents, who dismissed Clark Kerr, the university’s president, whom Mr. Roth had supported. Mr. Roth opposed Reagan’s education ideas as “high simplicity” and in 1974, as Reagan was preparing to leave office, Mr. Roth deliberately showed up late so he would not have to vote on a resolution praising the governor.
In his own race for governor, in 1974, Mr. Roth placed fourth in a crowded Democratic primary with 10 percent of the vote. The winner, Jerry Brown, served as governor until 1983 and was again elected to the post in 2011.
In San Francisco, where he lived for many years, Mr. Roth led planning and education advocacy groups and was so generous to philanthropic causes that Herb Caen, the Chronicle columnist, called him “saintly.”
His most visible contribution came in 1962, when he and his mother, Lurline Matson Roth, bought the old Ghirardelli chocolate factory in the Fisherman’s Wharf area after the company had moved. Some San Franciscans feared that the factory site would be used to build apartments, but Mr. Roth said the purchase was about “conserving the historic character of the city rather than just investment for profit.”
After spending $2.5 million for the property, the Roths spent millions more to restore the original buildings and courtyard and surround them with terraces of trees and flowers. The reimagined site became home to shops (including one still selling Ghirardelli chocolate), restaurants, a museum, a theater and a nightclub. It is now considered a forerunner of a movement to convert abandoned industrial properties into tourist attractions, what urban planners call “adaptive reuse.” It is listed on the National Historic Register.
The Roths sold the property in 1982 for an estimated $20 million.
Mr. Roth also helped found the Ploughshares Fund, which gives grants to support antiwar efforts. He was president of what is now the San Francisco Museum of Modern Art and a director of the American Civil Liberties Union.
His death was confirmed by his grandson, William McCauley. He is survived by his wife, the former Joan Osborn; his sister Lurline Coonan; his daughters Jessica, Maggie and Ana, all with the last name Roth; six grandchildren; and three great-grandchildren.