Bordewich was born in New York City in 1947, and grew up in Yonkers, New York. While growing up, he often traveled to Indian reservations around the United States with his mother, LaVerne Madigan Bordewich, the executive director of the Association on American Indian Affairs, then the only independent advocacy organization for Native Americans. He holds degrees from the City College of New York and Columbia University. He has been an independent writer and historian since the early 1970s. He also served for brief periods as an editor and writer for the Tehran Journal in Iran, in 1972-1973, a press officer for the United Nations, in 1980-1982, and an advisor to the New China News Agency in Beijing, in 1982-1983.