The Sinsinawa Dominican Congregation of the Most Holy Rosary was founded on Aug. 4, 1847, by pioneer priest Father Samuel Charles Mazzuchelli, OP, along with two women, Sisters Seraphina and Ermeline, entering. Two more women joined the fledgling community in December 1847. At the time of Father Samuel’s death in 1864, the number had increased to 23, and by the mid-1870s, there were 100 Sisters, staffing schools in five dioceses.
By the end of the 19th century, 389 professed sisters served in 30 locations throughout the Midwest. New missions proliferated, a pattern that would continue into the 20th century. Five academies were founded and parish grade schools were assigned to the Congregation in Chicago and Milwaukee. There were also new missions in small towns of northern Illinois, and as far west as Denver.
To accommodate the growing community, Mother Emily Power aggressively expanded the Mound facilities, including a new Academy building in 1882 and the four-story convent and novitiate building in 1900.
In 1901, Mother Emily accepted five Sisters of the Holy Ghost to the Congregation after their community in Rockwell, Iowa, disbanded. This set a pattern for similar arrangements later. In 1995, 36 new names were added to the membership rolls with the merger of the Sinsinawa Dominicans and the Spokane Dominicans.
Mother Emily laid a strong foundation for the Congregation between 1867–1909. After her, Mother Samuel Coughlin built it into one of the largest Congregations in the United States. During her 40-year tenure, the Congregation grew annually in number of members, in places served, and in gradual diversification of ministry—although teaching remained the main ministry. More than 1,450 Sisters made profession to her. Membership increased from 617 in 1910 to 1,547 in 1949, and the number of new schools increased from 41 to 102. The Sisters founded Edgewood College in Madison, Wisconsin and Dominican University of Illinois.
The 1950s and 1960s saw continued growth and expansion to accommodate the educational needs of the baby boom generation. Membership peaked at 1,983 in 1966, and declined to 1,606 by 1973. Today, there are more than 600 active Sinsinawa Dominican sisters.
Sinsinawa Dominican sisters are dedicated to preaching and teaching the Gospel, believing that at the heart of ministry is relationship. The sisters are committed to participating with others to build a holy and just society in the United States and abroad through ministry, or service to others. They are called to a wide variety of ministries: some are teachers, counselors and caregivers. Others are doctors, lawyers and pastoral ministers. Currently, their missions outside the U.S. include Mexico, Bolivia, Guatemala, Italy, and Trinidad and Tobago. The order's home, Sinsinawa Mound, is located in southwest Wisconsin.