Adelia Antoinette Field Johnston (1837-1910), educator and activist, was born to Leonard Field (1809-1849) and Margaret Gridley (1813-1887) in Lafayette, Ohio on February 5, 1837. Her parents moved west to Lafayette from Rodman, Jefferson County, New York because her father was eager to “take up” land, and her mother was ready to develop a teaching career. Although they had never met in New York, they shared mutual interests in moving to the new colony, and eventually developed a life-long companionship. Upon her father's death in Chester, Ohio on September 12, 1849, Adelia moved to Oberlin with her mother and younger sister at the age of thirteen. At fifteen, she entered the preparatory side of the Ladies' Course at Oberlin College (1852-1856).

The young Adelia received a literary degree from Oberlin College in 1856, and shortly thereafter, left to pursue a teaching position at Mossy Creek in Tennessee. During a return visit to see her mother in Oberlin (September 1858), Adelia drove a buggy with her mother to purchase some books at James M. Fitch's (Sunday school superintendent) bookstore. There, she overheard Simeon Bushnell (clerk and printer) and Henry E. Peck (lawyer) discussing with Fitch the rescue of fugitive slave John Price. Adelia and her mother, Margaret, quickly drove to Wellington, and were the first women on the scene of the Oberlin-Wellington rescue. Freelance writer Nat Brandt has labeled Oberlin, "the town that started the civil war." Upon returning to Tennessee that year, she felt compelled to conceal the fact that she had been a witness of the rescue freeing John Price, and was careful not to send mail to her home address in Oberlin.

Following teaching appointments at the Black Oak Seminary in Mossy Creek, Tennessee (1856-1859), Orwell Academy in Orwell, Ohio (1859), Kinsman Academy in Kinsman, Ohio (1862-1865), and the Academy of Scituate in Rhode Island (1865-68), Adelia studied abroad in Germany for two years and then returned to Oberlin in 1870 to become Principal of the Women's Department (succeeding Mrs. Marianne P. Dascomb) on the condition she be allowed to teach. Through this arrangement, she was the first woman to receive full membership from the Oberlin faculty. Among the Oberlin staff, her sponsors were James H. Fairchild, and Mr. and Mrs. James Dascomb.

As early as 1880, Johnston began to collect photographs (heliotype reproductions) and other materials of illustration during her many trips abroad as an effort to spur a local interest in art among the college and community. Johnston traveled abroad extensively and also hosted summer trips to Europe with Mary M. Wright (1877), Mr. and Mrs. Cyrus Grandison Baldwin (1881-1882), and Dr. and Mrs. Lucien C. Warner (1888). Her sponsorship of academic field trips to Europe (1892, 1894, 1897, 1899) and a Winter Term in Egypt (1903), complemented her already "graphic and illuminating" Art History and Architecture courses. Johnston served the College as Dean of Women until 1900 and as professor of Late Medieval History until 1907.

Johnston's influence on Oberlin College transcended the classroom. It was through Johnston that the Severance and Allen families became interested in Oberlin College. Donations for Baldwin and Talcott Cottages, Sturges Hall, the Warner Musical building, Spear Library, Lord Cottage, and Rockefeller Skating Center were received by the college as a result of Johnston's stewardship activity. Dean Johnston was always successful in making donors feel the pleasure of giving such financial support to Oberlin.

She gave herself unreservedly to college work until her retirement in 1907. Johnston announced her retirement during a Commencement '07 evening prayer, when she expressed that she had been unable "to do what ought to have been done as a citizen of the town, but relieved from the labors of deanship, promoting the welfare of the town and beauty of the community was possible."

During the last ten years of her life, Johnston continued to give lectures and publish essays concerning the welfare of the college and community, signing them as Madame Johnston. One of her major contributions to the town of Oberlin was her role in organizing the Oberlin Village Improvement Society, as is fully documented by Barbara Christen in City Beautiful In a Small Town, in collaboration with Oberlin College trustee Charles Martin Hall. The objective of the Society, for which she served as president, was to make the city a place "worthy of the college" by cleaning Plum Creek, creating a park system, improving sanitary conditions and beautifying the town in general.

Adelia Antoinette Field married James M. Johnston (OC '58) when she returned to Rochester, Ohio in August 1859. She pursued advanced studies with James at the Orwell School, where he served as the Principal until his enlistment in the Civil War in 1861. She volunteered as a nurse in a hospital not far from where James was stationed at Harper's Ferry. After developing a sudden cold for two weeks, James developed severe health complications from which he died on January 3, 1862. Adelia A.F. Johnston died on July 22, 1910, due to a cerebral hemorrhage that she had suffered five weeks earlier. Her beloved students and colleagues established the Adelia A. F. Johnston Fellowship in her honor.