Robert Ellsberg is the son of Carol Cummings and the American military analyst and whistleblower, Daniel Ellsberg. At age 19, Robert dropped out of college, intending to spend a few months with the Catholic Worker Movement. He stayed to become the managing editor of The Catholic Worker for two years (1976-8), a job that would introduce him to Dorothy Day and consequently would allow him to work with Day for the last five years of her life. This life-changing experience prompted him to convert to Catholicism.
In 1987 he began work as editor-in-chief of Orbis Books. He in theauthor of several books, including All Saints: Daily Reflections on Saints, Prophets, and Witness for Our Time, and the Saints’ Guide to Happiness. His book Blessed Among All Women tied a Catholic Press Association record by winning awards for Gender, Spirituality, and Popular Presentation of the Catholic Faith. He is the editor of the published diaries and letters of Dorothy Day. He currently resides in Ossining, New York with his wife and their three children.