| 2007 - 2008 | Mount St. Mary’s University celebrates its bicentennial. |
2002 - 2003 | Expansion of the Cogan Student Union Building into the William J. McGowan Center (comprising of student services in Cogan Hall and dining services in Patriot Hall) |
| 5 December 1999 | Bp. Keating Hall, the newest wing of the seminary, is dedicated. |
| 1995 | The Marion Burk Knott Auditorium is constructed. |
| Spring 1990-91 | Major renovations to McSweeny, Gallagher, and Mulcahy Halls give their present-day appearance. |
| Spring 1986 | Construction starts of the Knott “ARCC” across Route 15 from the main campus. |
| 11 October 1975 | Knott Academic Center (known as the “AC”) is dedicated. |
| 10 October 1975 | Mulcahy Hall, a wing of the seminary, is dedicated. |
| Fall 1964 | Ground broken for the Coad Science building. |
7 June 1961
| Ground broken for the Cogan Student Union Building (known for many years as the “SUB”). |
| 1960 | The Phillips Library is constructed. |
| Summer 1959 | Construction starts on Gallagher Hall, a wing of the seminary. |
| 5 November 1949 | Second college gymnasium is dedicated in the WWII aircraft hanger (obtained from military surplus the previous year). |
| 16 August 1907 | Ground is broken for the current Chapel of the Immaculate Conception. |
| 8 October 1806 | Cornerstone is blessed for McSweeny Hall in the seminary. |
| 18 October 1903 | Flynn Hall Gymnasium opens (currently used for the Dept. of Visual & Performing Arts). |
| 1900 | Echo Field is laid out in the former college vegetable gardens. |
| 11 January 1858 | McCaffrey Hall opens. |
| Spring 1844 | Construction is completed on Bruté Hall. |
| 6 October 1826 | Fr. John Dubois leaves the Mount on his way to Baltimore and his episcopal consecration as the third Bishop of New York. |
| 16 December 1825 | Dubois Hall is opened. |
| 22 June 1809 | Mother Elizabeth Ann Seton arrives in Emmitsburg from Baltimore with her first sisters (Daughters of Charity). |
| 6 October 1808 | Construction begins on Dubois’ school at Mount St. Mary’s. |
| 15 August 1806 | Fr. John Dubois dedicates his new church on the hillside above today’s Mount St. Mary’s University. |
| 1791 – 1806 | Fr. John Dubois works as a circuit-riding priest in Maryland and northwestern Virginia. |
| July 1791 | Fr. John Dubois emigrates to the United States of America. |
| 22 September 1787 | John Dubois is ordained a priest for the Archdiocese of Paris. |
| 24 August 1764 | John Dubois, Mount St. Mary’s founding father, is born in Paris, France. |
