In the late 1890's, bonanza farming was prevalent in the area. The equipment was dangerous and the work attracted people from all directions. Not only was the work dangerous but many sources of water were contaminated. The community and surrounding area felt it necessary to have a hospital to care for the sick and injured.

The ladies of the Mayville Churches united to form Union Hospital Society and it was incorporated on April 14, 1898. The first Board of Directors was elected.

The first hospital was used for 50 years. By the middle of the 1940's, the need for a new hospital building was very apparent. In 1951, the present Union Hospital building was put into service. Over the years, many improvements have been made to better accommodate the needs of the community for up-to-date medicine. In 1965, the north wing of the present hospital was added along with new space for X-ray and Lab. In 1976, a new Surgery suite, Administrative and Business Offices and front Lobby were built. Since 1976, the Nurses' Station has been replaced, and the Obstetrical Department modernized. In 1995-96, the Nurses' Station was relocated and enlarged and in the front of the hospital, a new, covered entrance was constructed. A new department in Cardiac Rehabilitation was established in 1994. Union Hospital has always tried to provide the services necessary and appropriate for area residents' health care needs. Union Hospital is a not-for-profit voluntary hospital, which means that it has no owners or people who receive profits. However, as in any business, profits are necessary to stay open. At the present time, the hospital enjoys an operational reserve of over one million dollars.

At the present time, Union Hospital is licensed for 25 acute care beds with 10 of these beds accommodating swing bed residents. The hospital has complete Lab, X-ray, and Surgical services with many ancillary services. The hospital's professional staff is made up of physicians from the MeritCare Health System in Fargo, North Dakota, who have a Mayville MeritCare Clinic in this community. The Clinic is staffed by three physicians and a family nurse practitioner and is serviced by specialist physicians from the Fargo, North Dakota clinics.