John Simmons Fentress, 56, a journalist who covered integration battles in the South, combat in Vietnam, the Supreme Court during the Warren years and the White House during Watergate, died of cancer Tuesday in his home in Chevy Chase.

Mr. Fentress was born in Maribel, N.C. After graduating from Wake Forest College in 1945 with a degree in history and government, he went to work as a deskman and political reporter for the Raleigh News and Observer. He worked in Raleigh 10 years before becoming an editorial writer for the Charlotte Observer.

His jobs with these North Carolina papers took him through the South of George Wallace, Big Jim Folsom and Lester Maddox during the turbulent early years of the civil rights movement, when, as he later wrote, "the diet was race and the crude salty politics of the South under pressure."

He was a Nieman Fellow at Harvard University in 1957-58.

He joined Time Magazine as its Atlanta bureau chief in 1961, staying there two years before moving to the magazine's Washington bureau to cover Robert Kennedy's Justice Department and later the Supreme Court near the end of Earl Warren's tenure as chief justice.

Mr. Fentress took over Time's Saigon bureau in 1966, while the massive buildup to American troops in Vietnam was underway. He covered the Vietnamese elections before returning to Washington and American politics in 1968.

During the presidential election years of 1968 and 1972, he charted the campaigns of Nelson Rockefeller, Edmund Muskie and Richard Nixon. He was named Time's chief political correspondent in 1972 before moving into the White House beat in January 1973. In recent years his beat was broadened to include a broad spectrum of political and government issues.

While Mr. Fentress spent his days in the office indulging his love of politics, he spent his weekends on the Eastern Shore indulging his love of duck hunting, and his evenings behind a trowel in his vegetable garden, or immersed in accounts of Civil War battles.

His survivors include his wife, Ruth Blount Fentress of Chevy Chase.