Blair Brown was born on April 23, 1946 in Washington, D.C. According to Blair, her father, Milton Henry Brown, was career CIA. Her mother, Elizabeth Ann Brown, was a teacher. She originally intended to have a career in the medical field. Instead, she trained at Canada's National Theatre School, graduating in 1969. Blair lived with actor Richard Jordan from 1976-1985. The couple had a son, Robert.
Blair went on to employment with the Stratford Shakespeare Festival Company where she received some acclaim. She then moved onto work with the New York Shakespeare Festival. It did not take long for Blair to move onto Hollywood. She had many television appearances during the 1980's.