On Oct. 21, 1944, Pope Pius XII established the Diocese of Steubenville. The bishops of Ohio decided that they would take the eastern part of the Diocese of Columbus and make it a missionary diocese. The new Diocese of Steubenville would consist of 13 counties in Southeastern Ohio and become a suffragan to the Archdiocese of Cincinnati. In March 1945, Msgr. John King Mussio, chancellor of the Cincinnati Archdiocese, was announced the first bishop of Steubenville.
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One year later, in March 1946, The Office of Social Ministry was established as a department within the Diocese of Steubenville. This new department would serve to oversee humanitarian efforts in the newly formed Diocese. It would operate this way until receiving its own non-profit business classification in April of 1983 as The Office of Social Ministry, Diocese of Steubenville. This new business would continue to operate under the direction of the Bishop of the Diocese of Steubenville and would continue to receive assistance from the Diocese; however, it would now be recognized as its own non-profit with the ability to function in a manner that would be most efficient to serve those in the community.
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Over the years, The Office of Social Ministry would also begin collaborating with the Catholic Campaign for Human Development, Catholic Relief Services and The Diocesan Office of Social Concerns for the Catholic Conference of Ohio.
In January 1986, the Office of Social Ministry, Diocese of Steubenville would be re-named Diocese of Steubenville, Catholic Charities to reflect its new position as a member agency of the broader Catholic Charities USA.
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New leadership in 2020 would bring more changes to Catholic Charities, Diocese of Steubenville. The offices would be moved out of the Chancery and to the new Sacred Heart Center of Hope, a resource center created by Catholic Charities to allow for service expansion and coordination. The name change process was also started once again and May of 2021 would see the final name change to Catholic Charities of Southeastern Ohio to reflect the new director’s vision to expand services to all 13 counties within the Diocese of Steubenville.