Terence A. Todman, who served as U.S. ambassador to six nations during a four-decade career in which he became the senior African American diplomat in the U.S. Foreign Service, died Aug. 13 at a hospital on St. Thomas in the U.S. Virgin Islands. He was 88.

His son Terence A. Todman Jr. confirmed the death and said he did not yet know the cause.

Mr. Todman, a native of the Virgin Islands, served as the U.S. ambassador to Chad, Guinea, Costa Rica, Spain, Denmark and Argentina, as well as assistant secretary of state for inter-American affairs during the Carter administration. He retired in 1993 with the prestigious rank of career ambassador.

Mr. Todman had joined the State Department in the early 1950s, he noted in an oral history, when “the only thing they had blacks doing . . . was serving as messengers and secretaries.”

He spoke candidly about the entrenched biases he experienced. During stateside training early in his career, he was prohibited from eating lunch with white colleagues. Later, despite expertise in Arabic and Arab affairs, he said that he felt relegated to African assignments.

Amb. Terence A. Todman died Aug. 13 at 88. (Frank Johnston/The Washington Post)

“I resented, and I still resent, the ‘ghetto’ assignment of blacks to Africa or to Caribbean nations,” he said in the oral history, taken in the 1990s for the Association for Diplomatic Studies and Training. “The United States still does that. We haven’t learned a thing over all these years.”

When he was named ambassador to Costa Rica in 1974, it was the first such appointment of an African American to a Spanish-speaking country, according to the Associated Press.

In 1977, he became assistant secretary of state under Cyrus R. Vance. In that role, Mr. Todman assisted with the Panama Canal treaties and became the first U.S. diplomat in 16 years to visit Havana.

As U.S. envoy to Spain from 1978 to 1983, he was the first African American to hold a major European ambassadorship. He later moved to Denmark, where, in 1986, he made news as a possible candidate for the ambassadorship to South Africa.

Reagan administration officials had indicated the president’s desire to send an African American to the country, then governed by the apartheid regime. Mr. Todman appeared at a news conference in Copenhagen, where he made remarks that were widely interpreted as criticism of administration policies.

President Ronald Reagan had expressed outrage at the apartheid system but opposed measures he described as “punitive sanctions” because they might limit U.S. diplomatic leverage and worsen the crisis.

“There isn’t any doubt about the firm opposition to apartheid that exists in the United States,” Mr. Todman said at the conference. He also said that official statements are not always believed by South Africans or others.

“I think once we have a policy that finds credibility with the South Africans, with the people of southern Africa and with the rest of the world, then we can start thinking of who is the very best person to go to South Africa to implement that policy,” he said. “I don’t think we are at that stage yet.”

Through a State Department spokesman, Mr. Todman said that his remarks, quoted in the news media, had been taken out of context. The ambassadorship went to Edward J. Perkins, an African American diplomat who had previously served as ambassador to Liberia.

Mr. Todman held his final post in Argentina, where he drew notice for addressing corrupt practices such as bribes that he believed obstructed U.S.-Argentine business. Earlier in his career, he had encountered the belief — unfounded, he discovered— that a black diplomat could not command the respect of foreign counterparts.

“The problem has been, and is, in the United States of America,” Mr. Todman said in the oral history. “The only opposition that I ever found, anywhere, has been from Americans.”

Terence Alphonso Todman was born March 13, 1926, on St. Thomas. His mother was a laundress and maid, and his father was a grocery clerk and stevedore.

During and after World War II, Mr. Todman served in the Army, including in the Pacific. He received a bachelor’s degree from the Inter-American University of Puerto Rico in 1951 and a master’s degree in public administration from Syracuse University in New York in 1952.

Although he had passed the required exams for entry into the State Department, he said that he was initially turned away by a personnel officer who noted his accent and said that the Foreign Service needed employees who were “100 percent identifiable as Americans.” Mr. Todman ultimately was hired anyway.

In the early years of his career, he served with the U.S. delegation to the United Nations and in India, Lebanon, Tunisia and Togo. After his retirement, he was a consultant and remained active in diplomatic affairs.

Survivors include his wife of 62 years, the former Doris Weston, of St. Thomas; four children, Terence Todman Jr. of New York City, Patricia Rhymer Todman of St. Thomas, Kathryn Todman Browne of Tampa and Michael Todman of St. Joseph, Mich.; a brother; and six grandchildren.

Reflecting on his career, Mr. Todman recalled in the oral history that when he was turned away from the lunch facility because of his race, he protested until the State Department made arrangements to accommodate him.

“I was considered a troublemaker,” he said, “and that was all right.”