Evangeline Bell Bruce, 77, the Georgetown hostess and diplomatic wife whose historic account, "Napoleon & Josephine, An Improbable Marriage," was published this year, died of a heart attack Dec. 12 at Georgetown University Hospital.

A tall, elegant woman who made best-dressed lists for years, Mrs. Bruce accompanied her husband, David K.E. Bruce, during a distinguished diplomatic career as ambassador to France, England, West Germany and NATO and envoy to China. Mrs. Bruce was known internationally for her beauty, her skill as a hostess and for transforming the decor of embassy residences and their gardens.

She and her husband "made a great diplomatic couple because she was so engaging," said her friend, Katharine Graham, executive committee chairman of The Washington Post Co.

"We were partners in every sense of the word," Mrs. Bruce told an interviewer for Vanity Fair magazine this year. "From day one . . . David expected me to be solely responsible for all the diplomatic entertaining, which forced me to get over my shyness."

Washington writer Sally Quinn wrote in 1987 that the era of Washington's most powerful hostesses, who included Mrs. Bruce, had pretty much passed. But in their time, they were "the ones who made a difference," Quinn wrote. "They were a special breed of women, reared, schooled and trained to understand the subtle arts of entertaining. They had the friendships, the contacts, the houses, the staffs, the silverware and the china to maintain a proper salon. . . .

"If they could bring together interesting, powerful men, those who were running the government, to exchange ideas and information in the privacy of their living rooms, that was an accomplishment in itself."

Mrs. Bruce told Quinn that the secret to being a good hostess was to "understand the elements of a party. The most important thing is the cast, which is the only thing that matters. And how they do the seating."

But in later years, Mrs. Bruce abandoned formal dinners in favor of Sunday brunches. It had gotten too hard, she said, to find equal numbers of men and women to pair at dinner.

Mrs. Bruce was born in England, the daughter of an American diplomat father and a British mother. Her father died when she was young, and her mother remarried, to a British diplomat. As a child, Evangeline Bell lived in Italy, Sweden, France, China, Japan, the Netherlands, Britain and Switzerland. Her early education was all in French, and over the years she became an expert on the French Revolution. She also wrote articles for Paris magazines.

Mrs. Bruce studied Chinese history and French literature at Radcliffe College but left in 1942 to work for the wartime Office of Strategic Services in London. Her boss there was David Bruce, whose first wife, Ailsa Mellon, was the daughter of Andrew W. Mellon, an American financier and former treasury secretary.

Evangeline Bell was Bruce's assistant and also was called on to forge passports and papers for Allied spies operating in Europe.

"It all seemed very romantic at the time," Mrs. Bruce told Washington Post staff writer Sarah Booth Conroy in a recent interview. "I had to invent all sorts of reasons why the bearer had a bicycle from one place and was riding it in another, for instance."

Evangeline Bell and David Bruce were married in 1945, established a home in Georgetown and moved to Paris three years later when he was named administrator of the Marshall Plan for European recovery. He became ambassador to France in 1949.

They returned to Washington in 1952 when he was named undersecretary of state but were living in Paris again the next year while he served as special envoy to the European Coal and Steel Community. He was appointed ambassador to West Germany in 1957.

Mrs. Bruce began her first book two decades ago. An account of France in 1795, it was never published. But after her agent suggested that she add biographies of famous people of the time, she began work on a novelistic description of the lives of Napoleon Bonaparte and his Martinique-born wife, Josephine.

Mrs. Bruce wrote of that era in France that it was "women who set the tone of the intellectual and political life of the capital . . . as arbiters of ethics and politics and molding public opinion. Women have never had so much power -- before or since."

The Washington Post's review of "Napoleon & Josephine" called it a "high-speed tour of the most complex period in French history . . . packed with fascinating, fleeting glimpses that seem to account for Josephine's distraction and inconsistencies."

David and Evangeline Bruce's seemingly charmed life crashed in 1975 with the devastating death of the oldest of their three children, Alexandra Bruce Michaelides, known as Sasha. Married for three months to a Greek citizen, Marios Michaelides, she died of a gunshot wound in the head at the Bruce family estate, the Gothic revival plantation house and farm called Stanton Hill, at Brookneal, Va.

The death was first ruled a suicide. But the investigation was later reopened, and Michaelides was charged with murder and with stealing furnishings of the estate. He had returned to Athens, however, and could not be extradited for trial.

Ambassador Bruce retired in 1976, and the couple resettled in Washington. He died the next year at the age of 79.

In the decades after her daughter's death, Evangeline Bruce dedicated much of her time to fund-raising for a Washington program for troubled youth, now known as Sasha Bruce Youthwork. Begun in 1974 as an outreach program, the organization now operates Sasha Bruce House, a round-the-clock shelter for young people, as well as five residences and other programs.

Mrs. Bruce enlisted the help of her friends on behalf of the organization, sponsored galas and movie screenings and made the project a focus of her life.

After the death of her husband, she spent summers in the Tuscany region of Italy and, later, the Provence region of France. She also spent part of each year at her apartment in London.

Mrs. Bruce is survived by two sons, David S. Bruce, who runs a bed and breakfast in the family home at Brookneal, and Nicholas C. Bruce of York Haven, Pa.; a sister, Virginia Surtees of London; and a granddaughter. JOHN BAXTER HOWES Rural Church Professor

John Baxter Howes, 87, a Methodist clergyman and a retired professor of rural church at Wesley Theological Seminary in Washington, died of cancer Dec. 12 at home in Emmitsburg, Md.

Dr. Howes was born in Ivyton, Ky. He graduated from Union College in Kentucky, then received a bachelor's degree in sacred theology from Boston University. He received a master's degree in sociology from the University of Maryland. He received honorary doctorates of divinity from Lycoming College in Pennsylvania and Union College.

His ministry included home mission work in Kentucky and Tennessee and work in Methodist parishes in Kentucky, Tennessee, Pennsylvania and Massachusetts. He was director of rural work in the Central Pennsylvania Conference of the Methodist Church.

In 1947, he joined the faculty of what was then Westminster Theological Seminary in Westminster, Md. He moved to Washington when the facility relocated to the District and became Wesley Theological Seminary in 1958.

He retired in 1979. On retiring, Dr. Howes moved from Gaithersburg to his country home in Emmitsburg. He later served five years as minister of Mount Bethel United Methodist Church in Foxville, Md.

Survivors include his wife of 64 years, Elizabeth Fisher Howes, and a daughter, Patricia Howes Bell, both of Emmitsburg. CAPTION: EVANGELINE BELL BRUCE