Born into an upper-class family in Massachusetts, Katharine Sergeant attended Miss Winsor's school in Boston and Bryn Mawr College. She married Ernest Angell in 1914; the couple were divorced in 1929 and she married E.B. White. In 1925, she became the first fiction editor at the fledgling publication The New Yorker and helped create its distinctive style and format. She was described as an extremely literate, elegant, and cultivated woman. James Thurber called her "the fountain and shrine of The New Yorker." She was credited with discovering the talents of many 20th century American writers. Her only book was published under the name Katharine S. White.