When Mr. Baker agreed somewhat reluctantly to step down to become Mr. Bush’s political adviser in his faltering re-election campaign in August 1992, Mr. Eagleburger was named acting secretary of state and ran the department. After losing the election to Bill Clinton, Mr. Bush officially named Mr. Eagleburger to the post. He served from Dec. 8, 1992, to Jan. 19, 1993. Only one other secretary served a shorter term, Elihu B. Washburne, who took office under President Ulysses S. Grant on March 5, 1869, and left 11 days later to head the American mission to France.

Overweight and a heavy smoker, Mr. Eagleburger did not fit the State Department mold. Time magazine wrote in 1992: “The common image of a U.S. secretary of state is that of Dean Acheson, Cyrus Vance, James Baker — a suave WASP lawyer, slender and urbane, who probably rowed at Yale or Princeton. But Lawrence Eagleburger, the new acting secretary, looks like the Michelin Man with a cane.”

His demeanor disguised an uncanny diplomatic ability to manage the difficult art of diplomacy, however. And his wit was legend. Asked at a Senate confirmation hearing if he had ever in public or private pinched a woman’s behind, Mr. Eagleburger replied: “Can I divide that into two questions?”

His influence in Washington grew as the top aide to Mr. Kissinger, who was named President Richard M. Nixon’s national security adviser in 1969 and secretary of state in 1973. In June 1969, he collapsed in his office from overexertion and was subsequently sent to NATO as head of the political section. He returned, though, in 1973 as Mr. Kissinger’s executive assistant. In that job, he was essentially responsible for running the State Department, which during the Watergate period effectively ran America’s foreign policy for a distracted White House.

Even though Mr. Eagleburger became known as “Kissinger’s man,” he was one of the few officials who had no fear of disagreeing with Mr. Kissinger. And he was able to win support throughout the bureaucracy.

Mr. Kissinger so trusted Mr. Eagleburger that he asked him to become involved in secret diplomacy with the Cubans when an abortive effort was made to see if relations could be established.

Despite Mr. Eagleburger’s close identification with the Republican Party and with Mr. Kissinger, President Jimmy Carter, a Democrat, picked him to be the ambassador in Belgrade, a place he had relished since his days as an economics officer in the American Embassy from 1962 to 1965.