Anne Seddon Kinsolving Brown, 79, an authority on military history of the period of the American revolution who assembled one of the world's great collections of military prints, died of cancer Nov. 21 at "Harbor Court," her home in Newport, R.I.

Mrs. Brown was born in Baltimore, the daughter of the Rev. Arthur B. Kinsolving, Episcopal bishop of that city, and Sally Bruce Kinsolving. She said her interest in military matters began in childhood, when she used to watch the fashionable "Dandy Fifth," as the Fifth Maryland Regiment is called, parade in period uniforms. But it was many years before this bore fruit in the work for which she is remembered.

After graduating from Bryn Mawr School, she was a reporter and music critic for the Baltimore News. She married John Nicholas Brown of Rhode Island, heir to one of the oldest fortunes in America and a notable philanthropist and patron of the arts. They raised a family and Mrs. Brown also undertook other responsibilities: among them was service as a trustee of the Providence (R.I.) Symphony Orchestra and membership on the visiting committee of the music department of Harvard University.

It was not until after World War II that she became active as a collector of military prints. In 1949, she and five others founded what is now the Company of Military Historians. Over the years she served as its president and held other offices. She was active in numerous other professional organizations.

Henry I. Shaw, chief historian of the Marine Corps and the president of the Company of Military Historians, said Mrs. Brown's collection is among the most complete in the world. Among its particular treasures is one of the four known copies of a book illustrating the uniforms of all the regiments of the Imperial Russian Army. It also includes the sketch books of the Rev. Percey Sumner, a noted authority on British uniforms, and the sketches of other important military artists.

As a historian, Mrs. Brown concentrated on the late 18th century and the Napoleonic period. Her publications include a two-volume edition of the diaries of the Comte de Rochambeau, the French nobleman and soldier who urged Gen. George Washington to undertake the operations at Yorktown, Va. This campaign, in which Rochambeau commanded a sizable French force, ended with the surrender of the British Gen. George Cornwallis. And so the Revolutionary War was won. The Rochambeau diaries appeared during the bicentennial period.

In 1965, Mrs. Brown was a lecturer on military history at the University of California. She was a member of the American Military Institute, the Society for Army Historical Research, the Military Historical Society of London and the advisory committee of the U.S. Army Military History Research Collection. Her own print collection was donated to Brown University.

In private life Mrs. Brown was a member of the national council of the Metropolitan Opera Co. and a director of the Spoleto Festival Foundation. She maintained a residence in Palm Beach, Fla., as well as her home in Newport. In the late 1940s, when her husband was assistant secretary of the Navy for air, she lived in Washington.

Mr. Brown died in 1979. Survivors include three children, retired Navy Capt. Nicholas Brown of Baltimore; J. Carter Brown, the director of the National Gallery of Art, of Washington, and Angela Bayard Fischer of Dedham, Mass.; a brother, Herbert L. Kinsolving of Annapolis; a sister, Mrs. Egbert G. Leigh III of Washington, and eight grandchildren.