The founding of the seminary was very nearly coincident with the founding of the Diocese of Cleveland. Bishop Amadeus Rappe was consecrated the first Bishop of Cleveland on October 10, 1847. After living for a short time in a rented house near the old Haymarket, the Bishop purchased a property on East 6th Street and St. Clair Avenue. The brick house on this property became his residence, and in 1848 the adjacent frame buildings were made into classrooms and became Cleveland’s first diocesan Seminary. By July of that year, there were eight students enrolled, all of whom lived with the bishop in the episcopal residence.

In the second year of its existence, the Seminary had 18 students and needed larger quarters. In September 1850, Bishop Rappe purchased a new site for his Seminary, a three-story frame building on a site 225 feet square, with frontage on Lake and Hamilton Streets. In 1853 a two-story brick structure was added to the west end of the building, and in 1856 another two-story brick structure was added to the west end
to serve as quarters for a classics department.

In 1859 Bishop Rappe began building a new Seminary on the same site. A brick building with the main part three stories high and with two flanking wings of two stories, the new Seminary was occupied in September 1860 by the Philosophy and Theology Departments while the older buildings became the site of the Classics Department, Saint Mary College. The Ordinary, Bishop Joseph Schrembs, broke ground for a new Seminary building on Ansel Road on March 19, 1924; the cornerstone was laid in May.

In the new building, Bishop Schrembs intended to include the Philosophy Program, which prior to that time had been in Cincinnati. In 1929, the Philosophy and Theology Departments were returned to the new Saint Mary, which then became Cleveland’s major Seminary with both a Philosophy Department and a Theologate. In 1954, Archbishop Edward F. Hoban transferred the Philosophy Program from Saint Mary to the newly established Borromeo Seminary of Ohio in Wickliffe, Ohio; since then, Saint Mary Seminary and Graduate School of Theology has been exclusively a graduate theologate.
On February 24, 1962, the Seminary became an affiliate of Washington, D.C.’s Catholic University of America, and students were eligible to receive the ecclesiastical degree of Bachelors of Sacred Theology (S.T.B). This arrangement continued to 1970.

On August 16, 1968, Saint Mary Seminary and Graduate School of Theology was incorporated by the State of Ohio. On September 13, 1968, the school was granted a “Certificate of Authorization received from the Ohio Board of Regents” to grant degrees in theological studies (Resolution 1969 –13). The members of the Association of Theological Schools (ATS) voted associate membership status to Saint Mary Seminary and Graduate School of Theology on January 15, 1969, and full accreditation was granted on January 14, 1971. On April 24, 1981, the Commission on Institutions of Higher Education of the North Central Association of Colleges and Schools accredited the Seminary.

In 1989, Bishop Anthony M. Pilla, bishop of the Diocese of Cleveland, inaugurated a thorough and lengthy consultative process to determine the future direction of priestly formation within the Diocese of Cleveland. After examining all the available options, the Presbyteral Council of the Diocese, the consultative body of priests for the bishop, recommended the establishment of a ministry training center to prepare not only priesthood candidates but permanent deacons and pastoral ministers as well. The bishop accepted this recommendation, and he appointed a Transition Committee to oversee the establishment of what is now known as the “Center for Pastoral Leadership, Diocese of Cleveland.”

On September 5, 1991, Saint Mary Seminary moved to the site of Borromeo Seminary of Ohio in Wickliffe, Ohio, to join this new center. The Center for Pastoral Leadership houses Saint Mary Seminary and Graduate School of Theology; Borromeo Seminary, which is now a formation program for college students; the Diaconate program; the Pastoral Ministry Office; and the Office of Continuing Education and Formation of Ministers. The five entities at the Center for Pastoral Leadership network and support each other while maintaining their distinct programs.