1888 through the early 1900s
1903: The hospital and a nurse training school opened in a building on the corner of Webster Avenue and Crooks Street. The hospital was originally sponsored by the Misericorde Sisters of Montreal, Canada.
1912: The first expansion included two additional stories and a new wing, and was finished in 1912.
1925: St. Mary's became the first hospital in the region approved by the American College of Surgeons, having cared for more than 20,000 patients by that point.
1960: Responding to the request of the Bishop of Green Bay for a Catholic hospital on Green Bay's growing west side, the Sisters relocated their entire campus to its current site on Shawano Avenue. The community greatly appreciated this move, especially having emergency services available west of the river.
1973: As the economics of health care delivery were changing dramatically, the Misericorde Sisters made the difficult decision to end sponsorship of St. Mary's in 1973.
1974: The Hospital Sisters of St. Francis, urged by Bishop Wycislo, assumed sponsorship in 1974. Since that time the Franciscans have worked diligently to maintain high-quality care and improve the capital and equipment base of the facility.
1979: Ground was broken for necessary new facilities.
1981: The new hospital opened as the first all private-room hospital in Northeast Wisconsin on Nov. 16, 1981.
1988: The Family Birthing Center was added in 1988 as well as an enlargement and renovation of St. Mary's Emergency Center.
1989: In July 1989, HSHS St. Mary's Hospital Medical Center and HSHS St. Joseph's Hospital of Chippewa Falls opened Libertas, a 24-bed inpatient facility for chemically dependent adolescents on the HSHS St. Mary's Hospital Medical Center campus.
1992 to Present
1992: A major ambulatory wing was added including outpatient surgery, advanced radiology and diagnostic services, respiratory care, pulmonary medicine and a new education center. Many doctors at HSHS St. Mary's Hospital Medical Center enjoy the convenience of a connected office complex that features modern services, dedicated parking and a private entrance. This part of the campus was developed during the 1990s and currently is home to more than 40 medical providers.
1996: HSHS St. Mary's Hospital Medical Center joined with HSHS St. Vincent Hospital, Beaumont-Webster Clinic and West Side Clinic to form Prevea Health Services, Inc., an integrated health care delivery system. Together, we provide the most advanced and comprehensive services available to people from all over Northeastern Wisconsin and the Upper Peninsula of Michigan. With a partnership among our physicians, staff and the community, we are well-positioned to keep pace with the changing health care needs of our community.
2010: A regional cancer center opened on HSHS St. Mary's Hospital Medical Center's campus in January 2010 as part of the Regional Cancer Collaborative. The center offers patients expanded space for chemotherapy with the addition of radiation therapy and other cancer treatment services provided in one convenient west-side location. The 115,000 square foot addition, along with a 22,000 square foot rooftop healing garden will be a state-of the-art model for cancer care throughout eastern Wisconsin.
2014: Opening of the Prevea Regional Orthopedics Center and remodeled One Day Services outpatient surgery center; also the year HSHS was officially added to all system hospital names.
2015: Hospital Sisters Ministries formed as the public juridic sponsor of HSHS.
2020: COVID-19 response, launch of the compensated CNA school, and establishment of Prevea Family Medicine Residency program with the Medical College of Wisconsin, Green Bay's first family medicine physician residency program.
2021: New Prevea St. Mary's Health Center opened at 1860 Shawano Ave. (3-story, 80,000 sq. ft.), plus two new pediatric-focused ED exam rooms open at St. Mary's.
2022: Prevea Surgery Center opens at 1830 Shawano Ave, Green Bay's first multi-specialty ambulatory surgery center.
2024: St. Mary's became the first in the region to offer robotic-assisted hip and knee replacement surgery with the ROSA® Robotic Surgical Assistant.
Present and Future
2025: A $270 million capital investment announced March 6, 2025, including the new tower at St. Mary's.