Pennsylvania, officially the Commonwealth of Pennsylvania, is a state located in the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Maryland to its south, forming the Mason-Dixon Line, West Virginia to its southwest, Ohio to its west, the Canadian province of Ontario to its northwest via Lake Erie, New York to its north, and the Delaware River and New Jersey to its east. Pennsylvania's most populous city is Philadelphia, and the state capital is Harrisburg. Pennsylvania is the fifth-most populous state in the country, with over 13 million residents as of the 2020 United States census. Pennsylvania has the ninth-highest by population density, and is the 33rd-largest by land area. The largest metropolitan statistical area is the Philadelphia metropolitan area, centered on Philadelphia, the sixth-most populous U.S. city. Pennsylvania's second-largest metropolitan area, Greater Pittsburgh, is centered in and around Pittsburgh, the commonwealth's second-largest city.
Pennsylvania was founded in 1681 through a royal land grant to William Penn, the son of the commonwealth's namesake. Before that, between 1638 and 1655, a southeast portion of the state was part of New Sweden, a Swedish colony. Established as a haven for religious and political tolerance, the British colonial-era Province of Pennsylvania was known for its relatively peaceful relations with native tribes, innovative government system, and religious pluralism. Pennsylvania played a vital and historic role in the American Revolution and the ultimately successful quest for independence from the British Empire, hosting the First and Second Continental Congress in Philadelphia, the latter of which formed the Continental Army commanded by George Washington in 1775, during the American Revolutionary War, unanimously adopted the Declaration of Independence the following year. On December 12, 1787, Pennsylvania was the second state to ratify the U.S. Constitution after Delaware.
The Battle of Gettysburg, fought in July 1863 around Gettysburg, was the bloodiest battle of the American Civil War with over 51,000 Union and Confederate casualties, and resulted in a repulsion of the Confederacy's invasion of the North. Throughout the late 19th and 20th centuries, the state's steel production and manufacturing-based economy contributed to the development of much of the nation's early infrastructure, including key bridges, skyscrapers, and military hardware used in U.S.-led victories in World War I, World War II, and the Cold War. In the 21st century, Pennsylvania has garnered the nickname "Cellicon State" for the central role of Philadelphia and Pittsburgh in the development of immunotherapies to treat different cancers.
Pennsylvania's geography is highly diverse. The Appalachian Mountains run through the center of the state, the Allegheny and Pocono mountains span much of Northeastern Pennsylvania, and close to 60% of the state is forested. Although Pennsylvania technically has no oceanic shoreline, it has 140 miles (225 km) of waterfront along Lake Erie and along the tidal Delaware River, the latter of which reaches the Delaware Bay, a marginal bay of the Atlantic Ocean.
History
Indigenous settlement
Pennsylvania's history of human habitation extends thousands of years before the foundation of the colonial Province of Pennsylvania in 1681. Archaeologists believe the first settlement of the Americas occurred at least 15,000 years ago, during the Last Glacial Period, though it is unclear when humans first inhabited present-day Pennsylvania. Between 10,000 and 16,000 years ago, Native Americans crossed the two continents, arriving in North America. Meadowcroft Rockshelter in Jefferson Township includes the earliest known signs of human activity in Pennsylvania and perhaps all of North America, including the remains of a civilization that existed over 10,000 years ago and possibly pre-dated the Clovis culture. By 1000 AD, in contrast to their nomadic hunter-gatherer ancestors, the native population of Pennsylvania had developed agricultural techniques and a mixed food economy.
By the time European colonization of the Americas began, at least two major Native American tribes inhabited Pennsylvania. The first, the Lenape, spoke an Algonquian language and inhabited the eastern region of the state, then known as Lenapehoking. It included most of present-day New Jersey and the Lehigh Valley and Delaware Valley regions in eastern and southeastern Pennsylvania. The Lenape's territory ended somewhere between the Delaware River in the east and the Susquehanna River in central Pennsylvania. The second tribe, the Susquehannock, spoke an Iroquoian language and were based in Eastern Pennsylvania along the Susquehanna River. European disease and constant warfare with several neighboring tribes and groups of Europeans weakened these two tribes, and they were grossly outpaced financially as the Hurons and Iroquois blocked them from proceeding west into Ohio during the Beaver Wars. As they lost numbers and land, the Hurons abandoned much of their western territory and moved closer to the Susquehanna River, and the Iroquois and Mohawk tribes moved further north. The Iroquoian Petun was northwest of the Allegheny River.
17th century
In the 17th century, the Dutch and the English claimed both sides of the Delaware River as part of their colonial lands in America. The Dutch were the first to take possession. By June 3, 1631, the Dutch began settling the Delmarva Peninsula by establishing the Zwaanendael Colony on the site of present-day Lewes, Delaware. In 1638, Sweden established the New Sweden Colony in the region of Fort Christina on the site of present-day Wilmington, Delaware. New Sweden claimed and, for the most part, controlled the lower Delaware River region, including parts of present-day Delaware, New Jersey, and Pennsylvania, but settled few colonists there.
On March 12, 1664, King Charles II of England gave James, Duke of York a grant that incorporated all lands included in the original Virginia Company of Plymouth Grant and other lands. This grant was in conflict with the Dutch claim for New Netherland, which included parts of today's Pennsylvania.
On June 24, 1664, the Duke of York sold the portion of his large grant that included present-day New Jersey to John Berkeley and George Carteret for a proprietary colony. The land was not yet in British possession, but the sale boxed in the portion of New Netherland on the West side of the Delaware River. The British conquest of New Netherland began on August 29, 1664, when New Amsterdam was coerced to surrender while facing cannons on British ships in New York Harbor. The conquest was completed in October 1664, when the British captured Fort Casimir in what today is New Castle, Delaware. The Treaty of Breda between England, France, and the Netherlands confirmed the English conquest on July 21, 1667, although there were temporary reversions.
On September 12, 1672, during the Third Anglo-Dutch War, the Dutch reconquered New York Colony/New Amsterdam, establishing three County Courts, which went on to become original Counties in present-day Delaware and Pennsylvania. The one that later transferred to Pennsylvania was Upland. This was partially reversed on February 9, 1674, when the Treaty of Westminster ended the Third Anglo-Dutch War and reverted all political situations to the status quo ante bellum. The British retained the Dutch Counties with their Dutch names. By June 11, 1674, New York reasserted control over the outlying colonies, including Upland, and the names started to be changed to British names by November 11, 1674. Upland was partitioned on November 12, 1674, producing the general outline of the current border between Pennsylvania and Delaware.
On February 28, 1681, Charles II granted a land charter to Quaker leader William Penn to repay a debt of £16,000 (around £2,100,000 in 2008, adjusting for retail inflation) owed to William's father. The transaction represents one of the largest land grants to an individual in history. Penn proposed that the land be called New Wales, but there were objections to that name, so he recommended Sylvania (from the Latin silva: "forest, woods"). The King named it Pennsylvania (literally "Penn's Woods") in honor of Admiral Penn. The younger Penn was embarrassed at this name, fearing that people would think he had named it after himself, but King Charles would not rename the grant. Penn established a government with two innovations, the county commission and freedom of religion, which were subsequently replicated in many of the Thirteen Colonies.
What had been Upland on the Pennsylvania side of the Pennsylvania-Delaware border was renamed Chester County when Pennsylvania instituted its colonial governments on March 4, 1681. Penn signed a peace treaty with Tamanend, leader of the Lenape, which began a long period of friendly relations between the Quakers and the Indians. Additional treaties between Quakers and other tribes followed. The Treaty of Shackamaxon of William Penn was never violated.
18th century
Between 1730 and when the Pennsylvania Colony was shut down by Parliament with the Currency Act in 1764, the Pennsylvania Colony made its own paper money to account for the shortage of actual gold and silver. The paper money was called Colonial Scrip.
The Colony issued bills of credit, which were as good as gold or silver coins because of their legal tender status. Since they were issued by the government and not a banking institution, they were interest-free, largely defraying the expense of the government and therefore taxation of the people. It also promoted general employment and prosperity, since the government used discretion and did not issue excessive amounts that inflated the currency. Benjamin Franklin had a hand in creating this currency, whose utility, he said, was never to be disputed. The currency also met with "cautious approval" by Adam Smith.
In 1740, Franklin also founded the University of Pennsylvania in Philadelphia. The university, one of nine colonial colleges, was the first college established in Pennsylvania and one of the first in the nation. Today, it is an Ivy League university, which is routinely ranked among the world's best universities. Dickinson College in Carlisle, founded by Benjamin Rush and named after John Dickinson, was the first college founded after Revolutionary War and the unification of the states. Established in 1773, it was ratified on September 9, 1783, five days after the Treaty of Paris.
James Smith wrote that in 1763, "the Indians again commenced hostilities, and were busily engaged in killing and scalping the frontier inhabitants in various parts of Pennsylvania. This state was then a Quaker government, and at the first of this war the frontiers received no assistance from the state." The ensuing hostilities became known as Pontiac's War.
After the Stamp Act Congress of 1765, delegate John Dickinson of Philadelphia wrote the Declaration of Rights and Grievances. The Congress was the first meeting of the Thirteen Colonies, which convened at the request of the Massachusetts assembly; nine of the 13 colonies sent delegates. Dickinson then wrote Letters from a Farmer in Pennsylvania, To the Inhabitants of the British Colonies, which were published in the Pennsylvania Chronicle between December 2, 1767, and February 15, 1768.
When the Founding Fathers convened in Philadelphia in 1774, 12 colonies sent representatives to the First Continental Congress. The Second Continental Congress, which began in May 1775, authored and signed the Declaration of Independence in Philadelphia, but when Philadelphia fell to the British in the Philadelphia campaign, the Continental Congress moved west, where it met at the Lancaster courthouse on Saturday, September 27, 1777, and then to York. In York, the Second Continental Congress adopted the Articles of Confederation, largely authored by Pennsylvania delegate John Dickinson, that formed 13 independent States into a new union. Later, the Constitution was written, and Philadelphia was once again chosen to be cradle to the new nation. The Constitution was drafted and signed at the Pennsylvania State House in Philadelphia, now known as Independence Hall, the same building where the Declaration of Independence was previously adopted and signed in 1776.
On December 12, 1787, Pennsylvania was the second state to ratify the U.S. Constitution, five days after Delaware became the first. At the time, Pennsylvania was the most ethnically and religiously diverse of the thirteen colonies. Because a third of Pennsylvania's population spoke German, the Constitution was presented in German so those citizens could participate in the discussion about it. Reverend Frederick Muhlenberg, a Lutheran minister and the first Speaker of the U.S. House of Representatives, acted as chairman of Pennsylvania's ratifying convention.
For about half a century, the Pennsylvania General Assembly met in the Philadelphia area before it began meeting regularly in Independence Hall in Philadelphia for 63 years. However, events such as the Paxton Boys massacres of 1763 had made the legislature aware of the need for a central capital. In 1799, the General Assembly moved to the Lancaster Courthouse.
19th century
The Pennsylvania General Assembly met in the old Dauphin County Court House until December 1821 when the Federal-style Hills Capitol, named for Lancaster architect Stephen Hills, was constructed on a hilltop land grant of four acres set aside for a seat of state government in Harrisburg by the son and namesake of John Harris, Sr., a Yorkshire native who founded a trading post and ferry on the east shore of the Susquehanna River in 1705. The Hills Capitol burned down on February 2, 1897, during a heavy snowstorm, presumably because of a faulty flue.
While awaiting the construction of a new capitol, the General Assembly temporarily convened at a nearby Methodist Church. Following an architectural selection contest, Chicago-based architect Henry Ives Cobb was commissioned to design and build the replacement structure, a project hindered by strict financial limitations imposed by its legislature. When they dubbed the roughly finished, somewhat industrial Cobb Capitol building complete, the General Assembly refused to occupy the building. In 1901, political and popular indignation prompted a second contest that was restricted to Pennsylvania architects; Joseph Miller Huston of Philadelphia was chosen to design the present Pennsylvania State Capitol that incorporated Cobb's building into a magnificent public work, finished and dedicated in 1907.
From 1857 to 1861, James Buchanan, a Franklin County native, served as the 15th U.S. president, the first president to be born in Pennsylvania.
Over three days, from July 1 to 3, 1863, during the American Civil War, the Battle of Gettysburg was fought near Gettysburg. The Battle of Gettysburg was the bloodiest battle of both the Civil War and of any battle in American history. The Union army's victory at Gettysburg also proved the Civil War's turning point, leading to the Union's victory two years later and the nation's preservation. Several months later, on November 19, 1863, then U.S. president Abraham Lincoln traveled to Gettysburg, where he participated in a ceremonial consecration of present-day Gettysburg National Cemetery and delivered the Gettysburg Address, a 271-word speech that is one of the most famous speeches in American history. During the Civil War, an estimated 350,000 Pennsylvanians served in the Union army, including 8,600 African American military volunteers.
The politics of Pennsylvania were for decades dominated by the financially conservative Republican-aligned Cameron machine, established by U.S. Senator Simon Cameron, who later served as Lincoln's Secretary of War. Control of the machine was subsequently passed on to Cameron's son J. Donald Cameron, whose ineffectiveness resulted in a transfer of power to Matthew Quay and later to Boies Penrose.
The post-Civil War era, known as the Gilded Age, saw the continued rise of industry in Pennsylvania. Pennsylvania was home to some of the largest steel companies in the world. Andrew Carnegie founded the Carnegie Steel Company in Pittsburgh and Charles M. Schwab founded Bethlehem Steel in Bethlehem. Other titans of industry, including John D. Rockefeller and Jay Gould, also operated in Pennsylvania. In the latter half of the 19th century, the U.S. oil industry was born in Western Pennsylvania, which supplied the vast majority of kerosene for years thereafter. As the Pennsylvania oil rush developed, Pennsylvania's oil boom towns, such as Titusville, rose and later fell. Coal mining, primarily in the state's Coal Region in the northeast region of the state, also was a major industry for much of the 19th and 20th centuries. In 1903, Milton S. Hershey began construction on a chocolate factory in Hershey, Pennsylvania; The Hershey Company grew to become the largest chocolate manufacturer in North America. Heinz Company was also founded during this period. These huge companies exercised a large influence on the politics of Pennsylvania; as Henry Demarest Lloyd put it, oil baron John D. Rockefeller "had done everything with the Pennsylvania legislature except refine it". Pennsylvania created a Department of Highways and engaged in a vast program of road-building, while railroads continued to see heavy usage.
The growth of industry eventually provided middle class incomes to working-class households after the development of labor unions helped them gain living wages. However, the rise of unions also led to a rise of union busting with several private police forces springing up. Pennsylvania was the location of the first documented organized strike in North America, and Pennsylvania was the location of two hugely prominent strikes, the Great Railroad Strike of 1877 and the Coal Strike of 1902. The eight-hour day was eventually adopted, and the coal and iron police were banned.
20th century
In the beginning of the 20th century, Pennsylvania's economy was centered on steel manufacturing, logging, coal mining, textile production, and other forms of industrial manufacturing. A surge in immigration to the U.S. during the late 19th and early 20th centuries provided a steady flow of cheap labor for these industries, which often employed children and people who could not speak English from Southern and Eastern Europe. Thousands of Pennsylvanians volunteered during the Spanish–American War. Pennsylvania was an important industrial center during World War I. The state provided over 300,000 soldiers during the war. On May 31, 1918, the Pittsburgh Agreement was signed in Pittsburgh, signed by Tomáš Masaryk and established Czechoslovakia as an independent nation.
In 1922, 310,000 Pennsylvania miners joined the UMW General coal strike, which lasted 163 days and shut down most of the state's coal mines.
In 1923, President Calvin Coolidge established the Allegheny National Forest under the authority of the Weeks Act of 1911. The forest is located in the northwest part of the state in Elk, Forest, McKean, and Warren Counties for the purposes of timber production and watershed protection in the Allegheny River basin. The Allegheny is the state's only national forest.
In 1922, the Benjamin Franklin Bridge began being constructed for the Sesquicentennial Exposition in Philadelphia being held in 1926. The chief engineer of the bridge was Polish-born Ralph Modjeski, the design engineer was Leon Moisseiff, the supervising architect was Paul Philippe Cret, and the construction engineer was Montgomery B. Case. Work began on January 6, 1922. At the peak of construction, 1,300 people worked on the bridge, and 15 died during its construction. The bridge was originally painted by a commercial painting company owned by David A. Salkind, of Philadelphia, which also painted the Golden Gate Bridge. The bridge opened to traffic on July 1, 1926, three days ahead of its scheduled opening on the nation's 150th anniversary. At completion, its 1,750-foot (533-meter) span was the world's longest for a suspension bridge, a distinction it held until the opening of the Ambassador Bridge connecting Detroit, Michigan, with Windsor, Ontario, Canada, in 1929.
During World War II, Pennsylvania manufactured 6.6 percent of total U.S. military armaments for the war, the sixth-most of the 48 states. Philadelphia Naval Shipyard served as an important naval base during the war, and Pennsylvania produced many of the war's most important military leaders, including George C. Marshall, Hap Arnold, Jacob Devers, and Carl Spaatz. During World War II, over a million Pennsylvanians served in the armed forces, and more Medals of Honor were awarded to Pennsylvanians than to individuals from any other state.
On March 28, 1979, the Three Mile Island accident was the most significant nuclear accident in U.S. commercial nuclear power plant history. The state was hard-hit by the decline and restructuring of the steel industry and other heavy industries during the late 20th century. With job losses came heavy population losses, especially in the state's largest cities. Pittsburgh lost its place among the top ten most populous cities in the United States in 1950, and Philadelphia dropped to the fifth and is currently the sixth-largest city after decades of ranking among the top three.
After 1990, as information-based industries became more important in the economy, state and local governments put more resources into the old, well-established public library system. Some localities, however, used new state funding to cut local taxes. New ethnic groups, especially Hispanics and Latinos, began entering the state to fill low-skill jobs in agriculture and service industries. For example, in Chester County, Mexican immigrants brought the Spanish language, increased Catholicism, high birth rates, and cuisine when they were hired as agricultural laborers; in some rural localities, they made up half or more of the population.
Stateside Puerto Ricans have built a large community in the state's third-largest city, Allentown, where they comprise over 40% of the city's population as of 2000.
In the late 20th century, as Pennsylvania's historical national and even global leadership in mining largely ceased and its steelmaking and other heavy manufacturing sectors slowed, the state sought to grow its service and other industries to replace the jobs and economic productivity lost from the downturn of these industries. Pittsburgh's concentration of universities has enabled it to be a leader in technology and healthcare. Similarly, Philadelphia has a concentration of university expertise. Healthcare, retail, transportation, and tourism are some of the state's growing industries of the postindustrial era. As in the rest of the nation, most residential population growth has occurred in suburban rather than central city areas, although both major cities have had significant revitalization in their downtown areas. Philadelphia anchors the seventh-largest metropolitan area in the country and one of the largest metropolitan areas in the world, and Pittsburgh is the center of the nation's 27th-largest metropolitan areas. As of 2020, the Lehigh Valley in eastern Pennsylvania is the nation's 69th-largest metropolitan area. Pennsylvania also has six additional metropolitan areas that rank among the nation's 200-most populous metropolitan areas. Philadelphia forms part of the Northeast megalopolis and is associated with the Northeastern United States. Pittsburgh is part of the Great Lakes megalopolis and is often associated with the Rust Belt.
21st century
During the September 11, 2001, terrorist attacks on the United States, the small town of Shanksville, Pennsylvania, received worldwide attention after United Airlines Flight 93 crashed into a field in Stonycreek Township, located 1.75 miles (2.82 km) north of the town. All 40 civilians and 4 Al-Qaeda hijackers on board were killed. The hijackers had intended to crash the plane into either the United States Capitol or The White House. After learning from family members via air phone of the earlier attacks on the World Trade Center, however, Flight 93's passengers revolted against the hijackers and fought for control of the plane, causing it to crash. It was the only one of the four aircraft hijacked that day that never reached its intended target and the heroism of the passengers has been commemorated.
In October 2018, the Tree of Life – Or L'Simcha Congregation, a conservative Jewish synagogue, experienced the Pittsburgh synagogue shooting, which resulted in 11 fatalities. On July 13, 2024, near Butler, Pennsylvania, an assassination attempt on the 45th President of the United States Donald Trump occurred. Since the inception of the 21st century, Pennsylvania has garnered the additional nickname of "Cellicon State" for the central role of Philadelphia and Pittsburgh in the development of immunotherapies to treat different cancers.
Geography
Pennsylvania is 170 miles (274 km) north to south and 283 miles (455 km) east to west. Of a total 46,055 square miles (119,282 km2), 44,817 square miles (116,075 km2) are land, 490 square miles (1,269 km2) are inland waters, and 749 square miles (1,940 km2) are waters in Lake Erie. It is the 33rd-largest state in the United States. Pennsylvania has 51 miles (82 km) of coastline along Lake Erie and 57 miles (92 km) of shoreline along the Delaware Estuary. Of the original Thirteen Colonies, Pennsylvania is the only state that does not border the Atlantic Ocean. With 86,000 miles of rivers and streams, Pennsylvania has the highest density of waterways of any state in the continental United States.
The boundaries of the state are the Mason–Dixon line (39°43' N) to the south, Twelve-Mile Circle on the Pennsylvania-Delaware border, the Delaware River to the east, 80°31' W to the west, and the 42° N to the north, except for a short segment on the western end where a triangle extends north to Lake Erie. The state has five geographical regions: Allegheny Plateau, Ridge and Valley, Atlantic Coastal Plain, Piedmont, and Erie Plain.
Climate
Pennsylvania's diverse topography produces a variety of climates, though the entire state experiences cool to cold winters and very warm, humid summers. Straddling two major zones, much of the state has a humid continental climate (Köppen climate classification Dfa or Dfb). The southern portion of the state has a humid subtropical climate. The largest city, Philadelphia, has a humid subtropical climate (Köppen Cfa).
Summers are generally hot and humid. Moving toward the mountainous interior of the state, the winter climate becomes colder, the number of cloudy days increases, and snowfall amounts are greater. Western areas of the state, particularly locations near Lake Erie, can receive over 100 inches (250 cm) of snowfall annually, and the entire state receives plentiful precipitation throughout the year. The state may be subject to severe weather from spring through summer into autumn. Tornadoes occur annually in the state, sometimes in large numbers, such as 30 recorded tornadoes in 2011; violent tornadoes, however, are rarer than they are in states further west.
Municipalities
Cities in Pennsylvania include Philadelphia, Reading, Lebanon, and Lancaster in the southeast, Pittsburgh in the southwest, and the tri-cities of Allentown, Bethlehem, and Easton in the central east, known as the Lehigh Valley. The northeast includes the former anthracite coal mining cities of Scranton, Wilkes-Barre, Pittston, Nanticoke, and Hazleton. Erie is located in the northwest. State College is located in the central region. Williamsport is in the north-central region with York, Carlisle, and the state capital Harrisburg on the Susquehanna River in the east-central region of the state. Altoona and Johnstown are in the state's west-central region.
The state's three-most populated cities, in order of size, are Philadelphia, Pittsburgh, and Allentown.
Adjacent states and province
Ontario (Province of Canada) (Northwest)
New York (North and Northeast)
New Jersey (East and Southeast)
Delaware (Extreme Southeast)
Maryland (South)