Deane R. Hinton, center, in the capital of El Salvador in 1983. (Robert Nickelsberg/Getty Images)

Deane R. Hinton, a career diplomat who served as U.S. envoy to five nations, most notably El Salvador in the early 1980s, where he presided over an embassy protected by sandbag gun emplacements amid civil war, died March 28 at his home in Escazú, Costa Rica. He was 94.

The cause was kidney infection and failure, said a son-in-law, Eric Chenoweth.

Mr. Hinton joined the Foreign Service in 1946, ascended to the rank of career ambassador and became known, journalist Christopher Dickey once wrote in Newsweek magazine, as “America’s closest approximation to the Roman Empire’s troubleshooting proconsuls.”

Mr. Hinton held his first ambassadorship under President Gerald R. Ford, serving as representative to what was then Zaire, where President Mobutu Sese Seko expelled him for an alleged assassination conspiracy. “Total nonsense,” Mr. Hinton said. “If I’d been out to get him, he’d have been dead.”

President Ronald Reagan selected Mr. Hinton to serve as ambassador to Pakistan and Costa Rica. President George H.W. Bush sent him to Panama in 1990, shortly after the U.S. invasion that removed President Manuel Antonio Noriega from power.

Mr. Hinton drew widest notice during his tenure in El Salvador, where he served from 1981 to 1983, and where he succeeded Robert E. White. White, serving under President Jimmy Carter, had aggressively denounced killings carried out by the Salvadoran military and its supporters.

Mr. Hinton generally voiced support for Reagan’s policy of providing substantial economic and military assistance to the ruling junta in its fight against leftist guerrillas. But in 1982, speaking in Spanish before the U.S.-Salvadoran Chamber of Commerce in San Salvador, he delivered a rebuke of the Salvadoran government, condemning political killings and kidnappings that he described as associated with “some elements of the security forces.” He compared rightist “gorillas” to leftist guerrillas.

“Every day we receive new reports of disappearances under tragic circumstances,” he said, in remarks uncharacteristically outspoken for an ambassador. “American citizens in El Salvador have been among the murdered, among the ‘disappeared.’ Is it any wonder that much of the world is predisposed to believe the worst of a system which almost never brings to justice either those who perpetrate these acts or those who order them?”

He said that if the Salvadoran government did not improve on human rights — a condition for the U.S. aid that in 1982 amounted to more than $230 million — “the United States, in spite of our other interests, in spite of our commitment in the struggle against communism, could be forced to deny assistance to El Salvador.”

The speech was a bombshell in El Salvador, where the Chamber of Commerce and Industry declared the ambassador’s remarks “appropriate to a delegate of the Roman Empire before a conquered people.” White House spokesman Larry Speakes said publicly that Mr. Hinton’s “statements do represent United States policy,” but an unnamed administration official told the New York Times shortly after Mr. Hinton’s address that “the decibel level had risen higher than our policy has allowed in the past.”

Interviewed later by The Washington Post, Mr. Hinton acknowledged that his speech represented a departure from the “quiet diplomacy” advocated by Reagan. “But there is provision for exception,” he added. “I decided the time had come to go public.”

In January 1983, Reagan certified sufficient progress in human rights for El Salvador to continue receiving aid. “Any president or any administration that thinks it would be a disaster if this country was taken over by a totalitarian Marxist regime is going to hesitate a long time and the evidence would have to be very strong before he decides not to certify,” Mr. Hinton said.

By April 1983, Mr. Hinton said that he was “weary” of the job. The next month, the administration announced that Mr. Hinton would be replaced. The post eventually went to Thomas R. Pickering, later ambassador to nations including Israel and Russia. Mr. Hinton retired in 1994.

Deane Roesch Hinton was born in Missoula, Mont., on March 12, 1923. He received a bachelor’s degree in social studies and economics from the University of Chicago in 1943 and served in the Army Signal Corps in North Africa and Italy during World War II.

His Foreign Service appointments including postings in Syria, Kenya, France and Belgium. In Guatemala and Chile, he oversaw USAID programs. In between ambassadorships, he served as U.S. representative to the European Union and assistant secretary of state for economic, energy and business affairs. He was the author of a memoir, “Economics and Diplomacy” (2015).

His first marriage, to Angela Peyraud, ended in divorce. His second wife, Miren de Aretxabala, whom he married in 1971, died in 1979.

Survivors include his wife of 34 years, Patricia Lopez of Escazú and Los Angeles; five children from his first marriage, Deborah Hinton of Garrett Park, Md., Christopher Hinton of Gettysburg, Pa., Jeffrey Hinton of Boulder, Colo., Joanna Hinton of Toledo, Ohio, and Veronica Hinton of New York City; five children from his second marriage, Pedro Arrivillaga of Santiago, Chile, Guillermo Arrivillaga and Juan Jose Arrivillaga, both of Bethesda, Md., Miren Arrivillaga de Aretxabala of Panama City and Maria-Louisa Arrivillaga of Key Biscayne, Fla.; two children from his third marriage, Sebastian Asturias Hinton of Los Angeles and Deane Patrick Hinton of Washington; 13 grandchildren; and five great-grandchildren.