David Chavchavadze, who died Oct. 5 at 90, was an American spy and a great-great-grandson of Czar Nicholas I of Imperial Russia.

As a CIA case officer, he specialized in clandestine communications and surveillance in matters affecting his ancestral homeland.

He did much of his work in Berlin in the years after World War II and at the start of the Cold War. His assignments included recruitment of Soviet agents.

By blood, he was connected to the Romanov dynasty that ruled Russia for 300 years. His mother, Nina, was a Russian princess and a great-granddaughter of Nicholas I, who was czar from 1825 to 1855. His father was Prince Paul of Georgia, a direct descendant of the former Caucasian kingdom’s last monarch, George XII, who died in 1801.

At the CIA, Mr. Chavchavadze fought the political heirs of the Bolshevik revolution that brought down the Romanovs in 1917. In 1918, the Bolsheviks executed Czar Nicholas II, his wife and their five children by firing squad in the cellar of a house at Yekaterinburg in the Ural Mountains.

David Chavchavadze in 1999. (Rich Lipski/The Washington Post)

Mr. Chavchavadze’s grandfather Prince Alexander Chavchavadze, a regimental commander in the czar’s army during World War I, was shot in a Georgian prison in 1931 by the Bolsheviks, who more than a decade earlier had overrun Georgia. His maternal grandfather, Grand Duke George Mikhailovich, a grandson of Czar Nicholas I, was shot in 1919 at the Fortress of St. Peter and St. Paul in Leningrad.

His espionage career, he wrote in a memoir called “Crowns and Trenchcoats,” was spurred by a desire to “do something about the dangers of international communism.”

David Paul Chavchavadze was born on May 20, 1924, in London, where his parents, as members of the Russian nobility, had sought refuge from the revolution.

His father was a fiction writer and a translator of writing from Georgian into English. He also worked for the Cunard shipping line, which in 1927 transferred him to New York.

In the United States, the family had social connections in the “white Russian” emigre community but little money. David Chavchavadze attended the private Phillips Academy in Andover, Mass., on scholarship and then Yale University.

In addition to his Romanov forebears, and ties to the Georgian monarchy, he also was descended from the royal families of England, Denmark and Greece. “That and 75 cents will get you a cup of coffee,” he told the New York Times back in the days when anyone could get a cup of coffee for 75 cents.

His education at Yale was interrupted by Army service in Alaska during World War II. He was a U.S. liaison officer to Red Army forces stationed in Alaska in those years but, more than three decades after the Russian Revolution, the Soviet soldiers bore him no overt antipathy for his aristocratic ancestry. According to his memoir, they addressed him as “Comrade Prince.”

He served in the Army in Berlin after the war, then returned to Yale and graduated in 1950. He soon joined the CIA, having been recruited by an old Yale friend.

As a case officer in the field, he wrote in his memoirs, “the work is just about endless. . . . After an agent (informant) meeting, the case officer writes up a contact report, time and place of meeting, next meeting, what was said, agent morale and family situation, possibilities of access to new information, securities difficulties real and potential, passing of money or operational entertainment, etc.”

Those duties were usually in addition to the work required for the case officer’s “cover job,” such as employment in a commercial or agricultural mission. He retired in 1974, having spent the last nine years of his career traveling around the world to meet with Soviet defectors.

In addition to his interests in singing and playing guitar, he worked on his memoirs and traced the history of Russian nobility in a 1989 book, “The Grand Dukes.” He lived in Northwest Washington in a house so often frequented by Russian emigres and dissidents that it became known informally as “Dissident Arms.”

He died at a health-care center in Potomac from kidney failure and dementia, said his wife of 35 years, Eugenie de Smitt Chavchavadze.

Mr. Chavchavadze’s earlier marriages to Helen Husted and Judith Clippinger ended in divorce. Survivors include two daughters from his first marriage, Maria Chavchavadze of Wellfleet, Mass., and Alexandra Chavchavadze of Brooklyn, N.Y; two children from his second marriage, Catherine Chavchavadze Redpath of Manhattan and Michael Chavchavadze of Watkins Glen, N.Y .; a stepson, Paul Olkhovsky of Arlington; and six grandchildren.

Not until 1966, when his son, Michael, was born at George Washington University Hospital, was there a male Chavchavadze heir, necessary under protocols of nobility to carry the family name into the next generation.

“ ‘Hurrah,’ said my mother on the phone,” David Chavchavadze wrote in his memoirs. “The dynasty is saved.”