On May 10, 1775, the Second Continental Congress assembled at the Pennsylvania State House after the Battles of Lexington and Concord marked the beginning of the American Revolutionary War.

[12] Congress adopted the Olive Branch Petition in July 1775, which affirmed American loyalty to Great Britain and entreated King George III to prevent further conflict.

[17] On June 11, the Second Continental Congress appointed the Committee of Five, which included John Adams of Massachusetts, Benjamin Franklin of Pennsylvania, Thomas Jefferson of Virginia, Robert R. Livingston of New York, and Roger Sherman of Connecticut, to draft an official declaration of independence.

[18][self-published source] Congress unanimously adopted its final version of the Declaration on July 4, marking the formation of the United States of America.

[21] At the Annapolis Convention in September 1786, the delegates asked for a broader meeting to be held the next May in Philadelphia to address the regulation of trade and the structure of the government.

[24] At the convention, delegate James Madison presented the Virginia Plan, which proposed a national government with three branches with proportional representation.

In response, William Paterson designed the New Jersey Plan, which proposed a one-house (unicameral) legislature in which each state, regardless of size, would have one vote, as under the Articles of Confederation.

Robert Morris, a representative from Pennsylvania, convinced Congress to designate Philadelphia as the temporary capital city of the United States federal government.

Despite its crucial role in the nation's founding, the site served most of its useful life as a municipal facility after the federal government relocated to the District of Columbia.

[35] The district's importance had waned with the western movement of City Hall and other institutions, but it remained an active and occupied business center.

[33] Kelsey and Boyd were motivated by a desire to create a fitting setting for Independence Hall, lessen the fire hazard, reduce congestion, and beautify the entire district.

[36] The commencement of World War II led to a heightened sense of patriotism and urgency toward the protection of national monuments.

On March 16, 1959, it incorporated the Old Philadelphia Customs House (Second Bank of the United States), which had been designated a national historic site on May 26, 1939.

[41] Buildings surrounding the Mall include Congress Hall, Independence Hall, and Old City Hall to the south; the Philadelphia Bourse, the National Museum of American Jewish History, Christ Church Burial Ground, and the Philadelphia Mint to the east; the approach to the Benjamin Franklin Bridge to the north; and WHYY-TV, the Federal Reserve Bank of Philadelphia, the James A. Byrne Federal Courthouse (which houses the United States Court of Appeals for the Third Circuit and the United States District Court for the Eastern District of Pennsylvania), and the Rohm & Haas Building to the west.

His concept called for a 5-block mall extending from Chestnut to Callowhill Streets, and incorporating the approaches to the Benjamin Franklin Bridge.

His plan rejected, Lewis took the idea of a three-block mall to the Pennsylvania General Assembly, convincing legislators to build it as a state park and a monument to Pennsylvanians who had died in World War II, a concept that was never fully realized.

[44] Among these were the surviving walls of the President's House – the residence of George Washington and John Adams during the decade (1790–1800) that Philadelphia served as the temporary national capital.

[43] As plans emerged, retailers on Market Street resisted, arguing that the demolition was out-of-scale with the comparatively small landmark at its southern end.

Surrounding the fountains was a regularly spaced array of 700 honey locust trees planted 12'-6" by 18' on-center within a brick paved plaza.

In preparation for the Bicentennial celebration, the National Historical Park Advisory Committee made a proposal to have the Liberty Bell relocated outside of Independence Hall as the building was not able to accommodate the millions of visitors expected.

The initial plan of 1972 to relocate the Liberty Bell to South Third Street and Chestnut, two blocks east, was met with resistance from residents of the city.

It was this later idea that prevailed and the plans were drafted to construct the new glass and steel pavilion at the north end of the first block of Independence Mall near Market Street.

[50] In 1997, the NPS announced a plan to redesign Independence Mall, developed by the landscape architecture firm Olin Partnership.

The smaller parks along the eastern edge, some of which were raised above the central lawn, would provide more intimate gathering and sitting areas with extensive trees and other landscaping.

[51][52] A memorial at the corner of 6th and Market Streets outlines the site of the former President's House and commemorates the slaves who worked there, with foundations visible below ground.

In January 2024, the NPS announced a large suite of renovations planned to be completed by 2026, when the park and the city of Philadelphia expect an influx of visitors to celebrate the 250th birthday of the United States.