PAPennsylvania History

Pennsylvania at a historical glance

Pennsylvania was admitted to the Union on 1787, making it the 3rd state. As one of the original 13 colonies, Pennsylvania was a founding member of the United States. Its capital Harrisburg has been the seat of state government for most of the state's history. The state's history reflects waves of migration, conflict, and adaptation — from Indigenous civilizations through European colonization, statehood, the Civil War era, industrialization, civil rights, and the modern era.

Native peoples (pre-1500s)

For at least 10,000 years before European contact, Indigenous peoples lived across what is now Pennsylvania. Multiple distinct cultures developed in response to the region's geography — coastal peoples, plains peoples, river-valley peoples, mountain peoples — each with their own languages, governance, trade networks, religious practices, and agricultural traditions. Major Native nations in the region developed sophisticated political structures, sometimes spanning territory larger than entire modern states.

European colonization disrupted these civilizations dramatically. Disease (particularly smallpox, to which Native peoples had no immunity) wiped out an estimated 70-90% of Indigenous populations within 100 years of European arrival. Forced displacement, broken treaties, and the Indian Removal Act of 1830 further reshaped Native presence in the region. Today, Pennsylvania's Native heritage is preserved in place names (cities, rivers, counties), tribal nations within state borders, ongoing cultural practices, and an active sovereignty movement.

Colonial era and Revolution

As one of the 13 original colonies, Pennsylvania was central to the founding of the United States. British colonization of the region began in the 17th century. By the 1770s, colonial assemblies were resisting British taxation policies — the Stamp Act, the Townshend Acts, the Tea Act — and Pennsylvania sent delegates to the Continental Congress that declared independence on July 4, 1776.

Pennsylvania fought in the Revolutionary War (1775-1783) alongside the other 12 colonies and ratified the US Constitution between 1787 and 1790, depending on the specific date. The state's role in the American Revolution is commemorated through battlefields, historic sites, and museums throughout the state.

The 19th century in Pennsylvania

The 19th century was a period of dramatic change for Pennsylvania. Westward expansion, industrialization, immigration waves, railroad construction, the Civil War, Reconstruction, and the closing of the American frontier all shaped the state's development. Population grew steadily — sometimes through internal migration, sometimes through international immigration. The agrarian economy gave way (in many states) to industrial and urban economies. State governments expanded their roles: public education systems, infrastructure, public health, and (eventually) regulation of business all emerged in this era.

The 20th century

The 20th century brought two World Wars, the Great Depression, the New Deal, the Civil Rights Movement, the Cold War, the Space Race, the women's rights movement, and the rise of mass consumer culture. Pennsylvania participated in all of these in ways shaped by its local geography, demographics, and economy. Military bases, defense industries, federal investment in infrastructure (Interstate Highway System, dams, airports), and the GI Bill (which subsidized college education for veterans) all reshaped the state in the postwar era.

The modern era and demographics today

Today Pennsylvania has a population of over 10 million and is one of the mid-sized states. The capital is Harrisburg; the largest city is Philadelphia. The economy benefits significantly from oil and natural gas production. Agriculture remains an important sector. Political alignment has shifted over time and currently leans competitively as a swing state.

Historical sites and museums

Pennsylvania preserves its history through state parks, national monuments, historic districts, museums, and battlefields. The state historical society maintains records and offers educational programs. For a complete list of historic sites, visit the state's official tourism site or the National Park Service.

Pennsylvania notable firsts

• Site of Independence Hall (Philadelphia)
• One of the 13 original colonies

Pennsylvania vs similar states

How does Pennsylvania compare with 3 other states in the same region and size category?

State	Capital	Pop	Area rank	Admitted
Pennsylvania	Harrisburg	over 10 million	#33	1787
Maine	Augusta	1 to 5 million	#39	1820
Maryland	Annapolis	5 to 10 million	#42	1788
Massachusetts	Boston	5 to 10 million	#44	1788

Bordering states (6)

Pennsylvania shares borders with 6 other US states, listed alphabetically below. Each link goes to the dedicated state page.

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