During the American Revolutionary War, the church was selected as the site to hide and protect the Liberty Bell from seizure as British troops prepared the Philadelphia campaign, designed to attack and occupy the revolutionary capital in Philadelphia.

The Liberty Bell was hidden beneath floor boards in the church for nine months, from September 1777 until the British ultimately departed Philadelphia in June 1778.

Initially built as a log structure on its present-day site at 622 Hamilton Street in Center City Allentown in 1762, the original High German Evangelical Reformed Church building was replaced in 1773 with a simple brick structure, which was designed in a vernacular federal style and erected a few yards north of the first log church's location.

[2] In 1838, when Zion Reformed was enlarged, contractors may have incorporated the 1762 structure into the walls of the current building's boiler room.

The building was then enlarged further between 1886 and 1888 via gothic revival-style improvements made by architect Lewis Jacoby.