Joan Bingham, who played a key role in a merger that created the Grove Atlantic publishing house, then served almost three decades as its executive editor, died on Saturday at her home in Manhattan. She was 85. Her son-in-law, Joseph G. Finnerty III, said the cause was pneumonia. Ms. Bingham had already experienced glamour, accomplishment and tragedy when she helped found Grove Atlantic, which was formed in 1993 by the merger of Grove Weidenfeld and the Atlantic Monthly Press. She had married into the wealthy Bingham family, whose media holdings included the Kentucky newspapers The Louisville Times and The Courier-Journal, also in Louisville. Her husband, Robert Worth Bingham III, was thought to be destined for a prominent role in the family business, but he was killed in a freak accident in 1966. After that, Ms. Bingham made her own mark. In 1984 she was the founding publisher of The Washington Weekly, a spunky but short-lived publication that covered politics and culture in the nation’s capital. Later she edited a newsletter on economics in Paris. She then became the catalyst for Grove Atlantic. George Weidenfeld and Ann Getty (who died in September at 79) had created Grove Weidenfeld in 1986, incorporating the venerable Grove Press into the new company. Joan Williamson Stevens was born on March 5, 1935, in Steubenville, Ohio. Her father, Edward, was chief executive of United Oil Company in Pittsburgh, and her mother, Helen Williamson Stevens, was a homemaker. Joan Stevens grew up in Sewickley, Pa., a suburb of Pittsburgh, and graduated from Miss Porter’s School in Connecticut in 1953. Four years later she graduated from Connecticut College with a degree in art history. She was studying at the California School of Fine Arts in San Francisco when, during a summer session at Harvard University, she met Mr. Bingham. They married in 1960. Mr. Bingham enjoyed outdoor activities. In July 1966 the family was vacationing in Nantucket, Mass., and Mr. Bingham hoped to do some surfing. Fitting the surfboard into their rented car required rolling down the windows and laying the board crosswise in the vehicle, the ends protruding out the windows on either side. With Mr. Bingham driving, one end of the board clipped a park car, causing it to pivot, whipping the board into Mr. Bingham’s neck and killing him. Ms. Bingham remained a director of the family company (which sold its media holdings in 1986) but settled in Manhattan and Washington. Once she entered the book-publishing field, her homes in both cities, with their walls of bookcases, became frequent stops for those in the business. Ms. Bingham’s brief marriage to George Packard in the late 1970s ended in divorce. Her son, Robert Worth Bingham IV, died of a drug overdose in 1999. In addition to her daughter, Clara Bingham, she is survived by three grandchildren.