Mr. Bird, shown here sailing circa 1980, died June 2 at 94. (Family photo)

Eugene Bird was not yet 30 years old, a recent addition to the ranks of the State Department, when he was posted to the Israel-Jordan desk in Washington. It was a daunting assignment for an unseasoned diplomat in the wake of the 1948 Arab-Israeli War.

Newly on the job, Mr. Bird reported to Parker T. Hart, then director of the Office of Near Eastern Affairs, who asked the new hire if he had any preparation in the region’s treacherously complex history.

“I’m sorry, I’m a Swedish expert,” replied Mr. Bird, whose had Swedish heritage on his mother’s side.

“Have you read anything on the Middle East?” Hart wondered.

“I’m afraid I haven’t,” Mr. Bird confessed.

“Well, have you ever traveled there?” Hart pressed. The answer, again, was no. At that, Mr. Bird recalled, Hart sighed. “Well, maybe that’s what we need around here,” he remarked, “fresh, new minds.”

Mr. Bird, who spent the better part of his two-decade Foreign Service career in the Middle East, seeking to foster peace in a region that forever seemed to resist it, and later promoting a two-state solution to the Israeli-Palestinian conflict, died June 2 at a retirement community in Vancouver, Wash. He was 94.

The cause was complications from pneumonia, said his son, Kai Bird, a biographer whose books include the Pulitzer Prize-winning volume “American Prometheus: The Triumph and Tragedy of J. Robert Oppenheimer,” co-written with Martin J. Sherwin.

Mr. Bird’s Foreign Service career was a family affair, beginning with his first overseas posting, in 1956, as vice-consul in the Jordanian-controlled part of Jerusalem. The 1948 war had left the city split into a western Israeli sector and an eastern Jordanian one, a tense arrangement that would last until the Six-Day War of 1967.

His wife and young family joined him in the divided city, where they lived in the Arab sector and Kai Bird attended an Anglican Mission School in the Israeli sector, each day crossing the Mandelbaum Gate that marked the demarcation line. Kai Bird recounted the family’s experience in a 2010 memoir, “Crossing Mandelbaum Gate: Coming of Age Between the Arabs and Israelis, 1956-1978.”

In an oral history years later with the Association for Diplomatic Studies and Training, Eugene Bird said he became known as the “Mandelbaum Gate man,” making crossings in “our old Chrysler with Oregon license plates because we couldn’t accept license plates from either side,” he recalled.

In his memoir, Kai Bird described his father as “filled with an innate optimism about the post-war world.” That optimism carried him through events including the Suez crisis of 1956, when he helped evacuate Americans from the West Bank.

His wife and children departed on the last aircraft out of East Jerusalem, while Mr. Bird remained behind. His later postings included Beirut, Dhahran, Saudi Arabia, and Cairo, where he served as a commercial attache. During that assignment, he said, he was the last Foreign Service officer to visit Gaza before the outbreak of the 1967 war, in which Israel claimed the Gaza Strip, East Jerusalem and the West Bank, among other contested territory.

Mr. Bird spent the late 1960s and early 1970s in India as an economic officer before returning to the Middle East as a political and economic counselor in Jiddah , Saudi Arabia, helping to manage diplomatic relations during the 1973 Arab oil embargo. He retired from the State Department in 1975.

From 1993 to 2010, he led the Council for the National Interest, a nonprofit organization that seeks to counter what it considers unquestioning U.S. support for Israel.

“I have spent most of my adult life trying to help resolve this terrible conflict,” he wrote in a 2014 Los Angeles Times commentary. “We all know the bare outlines of an equitable compromise: two states with borders more or less along the lines of the 1967 armistice lines. The only alternative to diplomacy is endless war, and that is in no one’s interest. We must not reward aggression — by either side.”

Eugene Hall Bird was born in Spokane, Wash., on March 17, 1925, and grew up in Eugene, Ore. His parents, both former homesteaders in Montana, worked a variety of jobs to carry their family through economic hardship. In the oral history, Mr. Bird recalled telling Arabs that he, too, had lived in a tent, when his father was a migrant worker before the Depression.

After Navy service at the end of World War II, Mr. Bird received a bachelor’s degree in journalism in 1948 and a master’s degree in history in 1953, both from the University of Oregon.

Following his diplomatic career, he was Oregon chairman of Democrat Jimmy Carter’s successful 1976 campaign for president. Mr. Bird worked for General Electric in Riyadh, Saudi Arabia, and ran a personal computers business in Washington, where he lived until last year, before becoming president of the Council for the National Interest. He was a contributor to the Washington Report on Middle East Affairs.

Mr. Bird’s wife, the former Jerine Newhouse, was the founder of Partners for Peace, an organization that sponsored the national speaking tour “Women of Jerusalem: Three Women, Three Faiths, One Shared City.”

She died in 2012, after 64 years of marriage. Besides their son, of New York City, survivors include three daughters, Christina Macaya of Camas, Wash., Nancy Bird of Cordova, Alaska, and Shelly Bird of Alexandria, Va.; a sister; six grandchildren; and four great-grandchildren.