Ruth White was born on April 24, 1914, in Perth Amboy, New Jersey, and she spent her entire life in the same town. She was of Irish Catholic descent and attended St. Mary's High School before graduating with a bachelor's degree in literature from New Jersey College for Women, now Douglass Residential College at Rutgers University, in 1935.

While pursuing her acting career in New York City, she also taught acting and drama at Seton Hall University.

She studied acting with Maria Ouspenskaya and began her career in 1940 as an apprentice at the Cape May Playhouse. During World War II, she spent six months touring with a USO troupe in Alaska and the Aleutians. She was the leading resident actress at Bucks County Playhouse for five years starting in 1948.

Her Broadway debut came in 1949 with "The Ivy Green." Her career was briefly interrupted in the late 1950s when she cared for her ailing mother, but she made a strong comeback, appearing in off-Broadway plays by Samuel Beckett and Edward Albee.

She earned a Tony Award nomination in 1968 for her role in Harold Pinter's "The Birthday Party." Ruth White is best known for her roles in films such as "To Kill a Mockingbird" (1962), where she played the cantankerous Mrs. Dubose, and "Midnight Cowboy" (1969).

She also appeared in "The Nun's Story" (1959) and "Hang 'Em High" (1968). Her final film role was in "The Pursuit of Happiness," released posthumously in 1971. Ruth White won an Emmy Award in 1964 for her role in the Hallmark Hall of Fame TV movie "Little Moon of Alban" and an Obie Award in 1962 for her performance in "Happy Days."

Ruth White never married and passed away from cancer on December 3, 1969, at the age of 55. She was survived by her brothers, Richard and Charles, and her sister, Genevieve Driscoll.