Barbara J. Harrison, 88, who researched and wrote an account of her Scots-Irish ancestors, died Aug. 19 at the Ingleside at Rock Creek retirement community in the District.

The former Chevy Chase resident had Parkinson’s disease, her son, Coleman Harrison, said.

Mrs. Harrison was in her 70s when she picked up the family history project begun by her father and prepared a table of 3,000 ancestors. That work became a book in which she traced her family’s migration in the mid-1800s from County Fermanagh, in what is today Northern Ireland, to Rock Island, Ill. The volume was published privately in 2003 under the title “Three Brothers Johnston.”

Mrs. Harrison also wrote “Learning About India” (1977), a guide for American educators. She had lived with her husband — who was a Washington Post bureau chief in south and northeast Asia — for six years in India and for four years in Japan.

Barbara Kathreen Johnston was born in Kankakee, Ill. She graduated from the University of Illinois in 1944 with a degree in political science, and she did graduate work in political science at the University of Minnesota.

In the late 1940s, she worked for the United Auto Workers in Detroit as an assistant to labor leader Victor Reuther. A job with a Senate subcommittee on labor-management relations brought her to Washington in 1949.

Mrs. Harrison and her husband spent their summers at a vacation home on Little Cranberry Island, Maine.

Survivors include her husband of 60 years, Selig S. Harrison of Washington; a son, Coleman Harrison of Boston; a daughter, Kathreen Harrison of Thomaston, Maine; a brother; and four grandchildren.

— Emily Langer