Dr. William Worrall Mayo was an English immigrant who, after a decades-long struggle, became a well-known and highly-respected frontier doctor in Minnesota. At the beginning of the Civil War, Dr. Mayo attempted to obtain an appointment as a regimental surgeon in Minnesota but was rejected.
For this reason, when the U.S. Dakota War erupted on the Minnesota frontier in August 1862, he was available to accompany an expedition from LeSueur and St. Peter to relieve the besieged town of New Ulm. There, Dr. Mayo and several other physicians established emergency hospitals to care for the refugees and wounded. In 1863, Dr. Mayo was appointed examining surgeon of the draft enrollment board in Rochester, Minnesota. He fared well there and so moved his family to Rochester from LeSueur the following year. He quickly established himself as a Rochester community leader.
In 1883, in the wake of a tornado that devastated Rochester, Dr. Mayo came into contact with Mother Alfred Moes of the Sisters of St. Francis who eventually persuaded him help her establish a new hospital under her direction. With Dr. Mayo and his two physician sons as the hospital's only professional staff, this new institution was inaugurated in 1889 as St. Marys Hospital. By 1919, St. Marys Hospital had evolved into the Mayo Clinic, today one of America's most distinguished hospitals.