May graduated from Garfield High School in 1941 and started her nursing education at Seattle University. After Pearl Harbor, her Issei father was picked up, taken from family, and sent to a North Dakota camp for individuals considered "high risk" because he was a small businessman with a knit garments factory who traveled frequently to Japan.
May and three of her four siblings moved to Montana to avoid internment, and within a few months she moved to Chicago, where she met and later married her husband Vernon Hornback. They went on to have two children and settled in Madison, Wis., where May continued her education, always working while she attended school. She went on to become a nursing professor and national leader in nursing education.
For a time, she worked at the Veteran's Administration Hospital in Madison. She received her bachelor's degree from the University of Wisconsin School of Nursing in 1954, her master's degree in medical nursing from Western Reserve University in 1958, and her Ph.D. from the University of Wisconsin in 1970. She joined the faculty of the UW School of Nursing in 1956, and became one of the first nurse-educators to develop the use of television in teaching. In 1965 she joined the faculty at the UW Extension's Department of Nursing and for the next ten years, she co-directed the department's educational offerings to nurses through the statewide educational telephone network (ETN).
Dr. Hornback was nationally recognized as an educational innovator and in 1975, a year before her untimely death at age 52, she was appointed as the first chairman of the American Nurse's Association's National Accreditation Board for continuing education. Although she served as a consultant to several medical companies, educational institutions and NIH, she was always first and foremost an educator.
Her passion for learning and fighting discrimination lives on through the May Shiga Hornback scholarship at UW Madison established by her husband. The scholarship, for adults in nursing returning to school to further their nursing education, has a preference for minorities. Although she was not one to dwell on the past, she learned from it. Her own experiences during the World War II exclusion spurred her to take control of her life and help those who wanted maximize their abilities through education.