Frederick B. Dent, a South Carolina textile manufacturer who in the mid-1970s was President Richard M. Nixon’s secretary of commerce and President Gerald R. Ford’s special representative for United States trade negotiations, died on Dec. 10 in Spartanburg, S.C. He was 97.

His daughter, Pauline Dent Ketchum, confirmed the death, at the Spartanburg Medical Center, on Monday.

A soft-spoken businessman who advocated free trade and an end to most protectionist tariffs, Mr. Dent was commerce secretary from 1973 to 1975, bridging the Nixon and Ford administrations. He became Ford’s trade representative, with cabinet and ambassadorial rank, from 1975 to 1977, when the Republicans surrendered the White House to the Democrats and President Jimmy Carter.

In April 1973, two months after being sworn in as commerce secretary, Mr. Dent learned that his assistant secretary, Jeb Stuart Magruder, a former White House and Nixon campaign official, had resigned abruptly, accusing Attorney General John N. Mitchell and John W. Dean III, the White House counsel, of approving in advance the break-in and bugging of telephones at the Democratic National Committee headquarters at the Watergate apartment complex in Washington in 1972.