Dellinger was born in Wakefield, Massachusetts to a well-to-do family (his father was a lawyer and a prominent Republican). A Yale University and Oxford University student, he also studied theology at Union Theological Seminary. Rejecting his comfortable background, he walked out of Yale one day to live with hobos during the Depression. During World War II, he was a conscientious objector and anti-war agitator. In 2001, Dellinger led a group of young activists from Montpelier, Vermont, to Quebec City, to protest the creation of a free-trade zone. He died May 25, 2004, in Montpelier.