Holy Trinity Parish was founded in 1787 and is the oldest Roman Catholic community and house of worship in continuous operation both in Georgetown and in the larger city of Washington, D.C.

It is now called the Chapel of St. Ignatius, and is used for smaller ecclesiastical celebrations and as an auxiliary space for parish activities.

It was founded at the direction of Archbishop John Carroll, the founder of Georgetown College and, later, first Catholic bishop in America.

During the American Civil War, the federal government used the church as a hospital to treat more than 200 injured soldiers after the Second Battle of Bull Run in 1862.

[citation needed] President John F. Kennedy, a Roman Catholic, and his family frequently worshiped at Holy Trinity.

The church is also the place Joe Biden worshiped when he was Vice-President and again as President as well as Speaker of the House Nancy Pelosi while she was in Washington.

[1] This informal burying ground was established long before Holy Trinity Church bought its land.

[9] Many of the graves were relocated in 1817 when the burying ground closed, but by as late as 1917 (when Lower School was built) hundreds of them still remained.

But with each day of delay adding $10,000 to the cost of construction, Church officials decided graves that would be undisturbed by the project – such as those beneath the basement – should remain where they were.

When workers began clearing a "vacant lot" 100 feet (30 m) north of the Copley Hall excavation site, they rediscovered College Ground.

Historian Carlton Fletcher believes the 850 or so remaining bodies in College Ground either are still buried there, or were dug up and scattered when the Reiss Science Building (1962) and Edward B. Bunn S.J.

[1] Originally called the Upper Grave Yard, this cemetery was at the southern terminus of Tunlaw Road NW.

[16] The grounds were enlarged again in 1866 and 1867 (to its present size of 6 acres (24,000 m2)), a new sexton's house built, a receiving vault constructed, and a stone wall and new main gate erected on Wisconsin Avenue NW.

[1] The university attempted to move all remains and use the cemetery for real estate development in 1984, but was stopped after a successful lawsuit by the survivors of people buried there.

While it abandoned "perpetual care" (the highest degree of maintenance for a cemetery), it agreed to continue minimal mowing, weeding, and other landscaping needs.