At his inauguration as governor of Alabama in January that year, Wallace vowed to maintain "segregation forever", fulfilling the promise by barring the students. When the moment came, his willingness to enforce the pledge proved nominal; a carefully scripted performance, choreographed by the governor's office and the federal authorities in Washington, led by President John F Kennedy's attorney general brother Robert, allowed Wallace to state his position, while avoiding confrontation. Making the gesture, however, catapulted him on to the national scene and assured his re-election as a populist Democrat. In 1996, two years before his death, he apologised to Jones and asked for her forgiveness.
June 11 1963 was an oppressively hot day in Tuscaloosa, Alabama, the heat and humidity soaring to more than 100F - an apt metaphor for the climate of US race relations at the time. Vivian Malone and James Hood, the other black student wishing to enroll, waited in a car, while state troopers surrounded the university's Foster Auditorium, and Wallace stood in the doorway. Deputy attorney general Nicholas Katzenbach, flanked by federal marshals, went up to Wallace and asked him to abide by a federal court order.
Wallace read his statement citing states' rights to organise education, while Katzenbach telephoned the president, who federalised the Alabama national guard. The governor then left and the students, now under national guard protection, were admitted.
Later that night, the black civil rights leader Medgar Evers was gunned down outside his house in Jackson, Mississippi. President Kennedy had just delivered his landmark speech explaining the "moral crisis" facing America, and the need for intervention on behalf of the black students. His public confrontation with the south's most stringent segregationist put the Democratic party squarely on the side of the civil rights movement and changed the course of US politics for decades. Dr Martin Luther King's "I have a dream" speech came two months later at a civil rights march in Washington.
Vivian Malone grew up in Mobile, Alabama, the oldest of eight children. As a transfer student from the historically black Alabama Agricultural and Mechanical University (A&M), she was 20 when she and Hood were admitted to the University of Alabama. Early bomb threats did not materialise, though Hood left the university after two months "to avoid a breakdown". (He returned in 1997 to take a doctorate in higher education.) However, that November there were three bomb blasts, one only four blocks away from Malone's dormitory. "I was never afraid," she recalled. "I did have some apprehension in my mind, though, especially having gone to segregated 'separate but equal' schools."
After Evers' murder, Malone's resolve grew stronger. "I decided not to show any fear and went to classes that day," she said. One of her strongest memories was of how white students refused to make eye contact with her or return her smile. She credited her solid upbringing and strong religious belief for the strength to challenge segregation, having set her mind simply on "going to class and doing the best I could".
When, in 1965, she received a degree in business management, she became the first African-American graduate in the university's 134-year history - the first black student had been Autherine Lucy, who, in 1956, sought a master's degree in library science, only to be suspended and later expelled, ostensibly for her own safety, after three days of rioting and threats.
After graduation, Malone had difficulty finding work in Alabama. She moved to Washington to work in the civil rights division of the US justice department, and later became director of civil rights and urban affairs, and director of environmental justice, at the environmental protection agency. She retired in 1996.
Malone met her husband, Mack Jones, when, as a local student, the university hired him to be her driver. He later became an obstetrician, and died last year. She said recently: "Walking through the door that had been closed to me and others of my colour was a step toward ending segregation in the south. I thank God for selecting me for that purpose." The student body of the University of Alabama is now about 13% black.
Jones is survived by her son Michael and daughter Monica.
· Vivian Juanita Malone Jones, civil rights pioneer and civil servant, born July 15 1942; died October 13 2005