Isabella Garnett was born in Evanston in 1872 and received a nursing degree from Provident Hospital and Nurses Training School in 1895. She later graduated with a medical degree from the College of Physicians and Surgeons (now the University of Illinois College of Medicine) in 1901, making her one of the first female African American physicians in Illinois. Garnett returned to Evanston and married Dr. Arthur Butler in 1907. The couple opened the Evanston Sanitarium and Training School in their house at 1918 Asbury Avenue in 1914. Established for the care of African Americans in Evanston, the Sanitarium was one of only four hospitals in the Chicago area that would admit black patients at the time. The couple managed the fourteen-bed hospital until the untimely death of Butler in 1924. Thereafter, Garnett continued to manage the hospital until 1928 when she helped form the Community Hospital of Evanston.