[1] Though Catholics had been present in the Province of Maryland from its establishment in 1634 by the Lord Baltimore, Cecil Calvert, the British penal laws forbade the open practice of Catholicism.

Following the repeal of the Penal Laws in 1776, Pope Pius VI established the Diocese of Baltimore, in whose territory the church laid.

[2] Designed by local architect John Tien, the building's façade features pilasters of the Ionic order.

"[1] The church's square bell tower was completed in 1857, consisting of three, one-story telescoping sections and being topped by a gold cupola and a finial cross.

[1] In 1912, in celebration of the church's 75th anniversary of its consecration, a painting of the Ascension of Jesus was commissioned by Severino Baraldi in the center of the ceiling.

The church's high altar is constructed of Egyptian and Italian marble, while each 17-foot (5.2 m) window is peaked with a bust of St. John the Evangelist.