If you like alternate history, there's more here.
The Central State's flag above, and the American flag below, with the lions of sacred Mount Nittany standing guard. At one time the American flag had thirteen stripes, prior to the absorption of the Northeast Extension, the Lower Counties, and The Shore (old style, Connecticut, Delaware and New Jersey respectively.)
From fair Henlopen in the South, and Franklinton, New Reading and Long Island. From Toledo in the Northwest where the prairies begin, and the industrial river metropolis of Huntington, the Central State looms large in history and in our hearts. From the beginning it was a microcosm of all of America. The culture and government of the United States was not always so dominated as it is today by the Keystone Kingdom. Indeed it is sometimes difficult to separate discussions of national politics from those of "Pee-Ay". But it is instructive to revisit the events that led to such an arrangement.
On the eve of the Revolution, there was no sure sign that Pennsylvania would come to dominate the Union just as the original crown colony of Virginia had until then dominated the colonies. But there was already a hint during the Seven Years War, when British officers who came to fight the French in the North American theater recognized, in print, that Virginians promised everything and delivered nothing, while for the Pennsylvanians it was the contrary. No surprise that the opportunist Washington was the first to engage the French (illegally killing a surrendered officer), hunker down at Fort Necessity, and quickly lose.
In August the strengthened militia fully ejected the Yankees and pursued them across the border into New York. Mifflin returned to the Confederated States capital at Annapaolis and made his impassioned speech, demanding "Can only the Pennsylvanian reckon justice?" The call was heard back home, and as the Pennamite army pushed the weakening Yankees back to the Hudson River, reinforcements continued to pour in. (The story of a fleeing Yankee taunting now-General Shoemaker that Pennamites couldn't swim, while delicious, is likely apocryphal.) Thus began the Crossing near Newburgh, the Glorious March, and the Forty Great Days. The swollen Pennamite Army pursued the haggard Yankees, first to Hartford, then turned back to New Haven where the final resistance was met and crushed. The Burning of New Haven and subsequent salting of the soil caused the victorious Pennamites to name the town built on its ashes New Carthage. The first new piece of the Central State had been assembled.
Fresh from their victory and with no serious organized opposition, Shoemaker made the then-controversial decision to continue along the coast to the harbor town of Franklinton (then called simply New York City; difficult though it is for us to believe today, Franklinton was at that time actually slightly larger than Philadelphia!) Of course, we were all shocked to learn based on recently discovered letters that Mifflin had essentially ordered him not to. Franklinton took a few days longer but finally fell; it is often simplistically imagined that the fighting stopped quickly and neatly, but for nearly two months the hunt-and-snipe naval warfare continued, with most of the guerilla fighting both in the streets of the main island Manhattan and in the forests of Staten Island, along with significant resistance from the converted commercial barges coming down the Hudson. At this point Mifflin issued demands to the Lower Counties (then, confusingly, called "Delaware" after a county in southeast Pennsylvania that always remained as part of the Central State) that they return to the fold, and they rejoined with a minimum of discussion. Getting New Jersey's delegates to agree was slightly harder but after the (now archaic-seeming) carve-outs were placed in the Act of Union, Pennsylvania now extended to the Atlantic. This is the basis for public wagering and the production of certain pork products being restricted to The Shore; a pig farmer at the negotiations named Charles Taylor insisted on the latter, and the pork rolls still bear his name. (It's a curiosity that The Shore's official name remains New Jersey, though mapmakers seem unconcerned with this.)
By October, other states had begun organizing their own militias, with Massachusetts in particular preparing for all-out war. Mifflin unilaterally moved the capital back to Philadelphia, and appealed to the other states to quickly send delegates that the Articles of Confederation could be amended, as winter was approaching. Revisionists occasionally deride this as an illegal move, but the Republic as it stands is founded on the agreements subsequently drawn up. (The grumbling of James Montgomery, the Rhode Island delegate, that he was rubber-stamping something to give it an air of legitimacy, gives us the phrase "like a Rhode Islander at the convention" for those who decry pointless ceremonies.) Mifflin began with tweaks to the articles which subtly gave the Central State the "first among equals" status it now not so subtly enjoys. But the work continued into the winter, and once there was snow on the ground, he went full bore - in particular, in adding an article outlawing slavery, which Pennsylvania had already done within its own borders, in a law written by Mifflin himself. Mifflin knew what he was doing in bringing out these amendments to his captive audience when the weather turned - hence, where an Englishman might talk about crossing the Rubicon, an American would quote Mifflin: "When the first flake strikes the Schuylkill."
The agrarian states in the South obviously balked, but Mifflin had anticipated this. A militia composed of the willing - not only the Pennamites from the Central State's expanded realm but also New England abolitionists, had already been dispatched south, going plantation to plantation, intercepting riders bringing news of their approach, and most importantly - conducting rendition of slaveowners. This is the most difficult part of Thomas Mifflin's legacy, but the results are not in dispute. When the brigade officer met with the plantation owner, the owner would be asked to sign a document freeing his slaves, and a petition to be submitted to the Final Congress demanding the abolition of slavery throughout the nation. Of course, most refused; they were then brought north, themselves to work in the chilly fields of Lancaster and Berks County and building roads and digging canals, with the only condition required for their release - signing those two documents. By 1785 there were few enough holdouts that the Emancipation Act was passed, closing a stained chapter of our history.
The British were no idle spectators and indeed, had expected the experiment in self-government to fail from its first days. Caught by surprise, they had provided only nominal aid to the Yankees in the fall of 1784, but they were taken off guard; not so the following year. The wealthy plantation owners of Virginia met with the British naval officers who came up that state's rivers at night, and the Battle of Williamsburg was a narrow Pennamite victory, when a detachment of troops came upon a squadron of British ships at anchor. Of the owners who were sought and captured as a result of their foreign involvement, we mostly remember Washington, whose service to the cause of independence will be forever marred by his willingness to consort with the enemy to keep human beings in chains. One wonders how long, in some other world, some of our other Virginian First Fathers (Titan oldngods to Mifflin, Patterson and Montgomery's Greek pantheon) would have continued the institution of slavery without the example of Washington to encourage them to emancipate. This incident resulted in the transfer of Virginia's mountain counties and Trans-Ohio lands to Pennsylvania, a transaction encoded directly in the Charter, and the Central State took the final form it has today.
The High Governor's two official residences. Above, at Ocean City in The Shore and below, in South Mountain, Berks County.
In 1786 the Charter was finalized by Franklin and signed by Mifflin, and the Republic of America was born, with Pennsylvania at its heart. Governor Mifflin finally achieved his title, formally transferring his responsibilities to head of the Central State's government rather than that of the nation. As a result, legally, "Governor of Pennsylvania" is de facto interchangeable with leader of the Republic of America, with the American President having a mostly ceremonial role, much like the king in a constitutional monarchy. Mifflin was followed by Patterson and Shoemaker, and during the terms of the Great Three, America pushed in every direction, not only expanding beyond the Mississippi but also taking England's possessions in Canada and the Caribbean and adding them to the Republic. As the Republic expanded within the North American continent, it found itself in a complex arrangement, with the Pennsylvanian-founded states like Ollinger and Yoder having a status akin to a Republican version of those in Europe ruled directly by the Holy Roman Empire, and independent states like New Mexico and California as duchies and principalities. The Pennamites appeared to be unstoppable, and this era produced William Pitt the Younger's frustrated statement about finding England's sins, so she could be absolved and saved from this new race of devils.
A subsequent history of Pennsylvania is necessarily a history of the world, given its immediate industrial expansion and its people's close ties with the many progressive German states, usually considered to have started with an overseas victory by a combined force of European and Pennamite troops over the French despot Napoleon at Austerlitz, where Napoleon was captured and executed. These ties only deepened over the next century. Despite a brief clash between east and west nearly erupting into full civil war over the use of "soda" versus "pop", and "youse" vs "yinz", Americans continue to be greeted the world over as "pennies", and immigrants continue to arrive in Philadelphia and take a picture as they order their first sauerkraut and scrapple in the Central State. The ongoing Wawa-Sheetz controversy seems intractable, but Pennsylvania has always synthesized its extremes and risen above them.
BACK FROM ALTERNATE HISTORY: WHY DID NEW YORK AND NOT PENNSYLVANIA BECOME THE EMPIRE STATE?
New York didn't dominate the Union to nearly the same degree as our fun alternate history of "Imperial Pennsylvania." (I liked "Central State" better than "Keystone" because it echoes the literal translation of China's self-confident name for itself, the Central Kingdom.) But New York is to some extent the first among equals on the East Coast, even if de facto rather than de jure. Why? As usual, a combination of geography and demography being destiny, and historical happenstance.
First, what do we mean by "empire state"? The biggest wealthiest city, and the most famous people. Let's start with the second one there. It often sticks out to me that Pennsylvania had so many fewer presidents than the states that surround it. Virginia has eight, Ohio has eight, and New York has five. Pennsylvania finally has a second - in an ironic twist, the first was Buchanan, the worst president in American history until the twenty-first century, and the second president from PA unseated the only president who was even worse than Buchanan.[1] Again, why?
Pennsylvania was settled by people from the Midlands of England and Germans.[2] The German religious migrants and Midlanders were a group that valued equality and an overall "flat" social organization which was a major contributor to the informality and salt-of-the-Earth directness of the overall American character, and the religious tolerance that Penn espoused fit them well. New York had a heavy influence from the more rigid settlers of New England who valued education much more than Pennsylvania's farmers - and, in real life, came directly into armed conflict with them in the actually quite real Pennamite Wars[3], which formed the branchpoint in our exercise here.
As to the second factor - geography - New York was already slightly bigger during the time of the Revolution, but this obviously just begs the question.[4] Why was New York already bigger? You might think it's because it's a little closer to Europe, so it was easier for European migrants to arrive there. True, but then why isn't Massachusetts the Empire State? The real reason is that New York has the Hudson, a navigable river that crosses the Fall Line, which can be sailed all the way to Troy. It was easier to get raw materials and get to markets and then later, with canals, onto the Great Lakes. Similar reasons account for the origins of Detroit as the center of the automotive industry and Seattle as the headquarters of Boeing (wood for material, and water for transport for the early aerospace industry.) While Pennsylvania does have shoreline on Lake Erie, it's across the significant and little-discussed Eastern Continental Divide, that divides the watersheds of the Atlantic and the Gulf of Mexico. Pennsylvania did build a canal later connecting the Delaware and Chesapeake but the Susquehanna (whose name, according to a humorous myth, means "mile wide, inch deep") is just not a useful river for transporting goods.
Years ago I was curious why Virginia, the cradle of presidents, ended up settling with the title of dominion rather than empire? You may have noticed that despite Jamestown being the oldest culturally ancestral settlement in America[5], our biggest densest cities are not in coastal Virginia. (We actually lost the location of Jamestown at one point!) But straight line extrapolation from single facts is always a fool's game. Virginia's first two centuries were strong ones - the military uniform Washington wore early in the Seven Years War actually implied Virginia was a equal part of the United Kingdom along with England, Scotland and Ireland (sorry Wales.) But after the Civil War, Virginia was relegated to partly a suburb of DC, and then, well, the rest of it. (I'm partial to Hampton Roads for reasons of childhood vacations, and Shenandoah National Park is cooler than you might realize, but the point is fair.) Virginia is a warmer Pennsylvania, but even worse, with a wider coastal plain between the Atlantic and the Fall Line. Why even worse? Because as the industrial age unfolded, its better climate and broader plains cursed it.[6] The first settlers were from the estates of southern England (Albion's Seed termed them Cavaliers) and served as the first Presidents, but the agrarian paradise that Jefferson envisioned (a chain of plantation mini-states that were either utopias or dystopias depending what color your skin was) was soon outcompeted in dollars, growth, and power by the industrial cities to the north. (I would be curious to look at a Gini calculation between Pennsylvania and Virginia landowners or a comparison of mean farm size between the two, but I'm going to call that the line where the professionals can take over.) And finally, if you think the Fall Line in Pennsylvania was hard to get over, try the Appalachians in Virginia. Some of those roads in Shenandoah wouldn't look out of place in the Sierras if not for the deciduousness of the forests.
Long live the Keystone State! May it ever shine in glory!
FOOTNOTES
[1] If you don't agree, I'm surprised that you were able to read this far, but surely it was slow going and you're likely mouthing your words as you read.
[2] Albion's Seed is an excellent book, which details how each region of colonial America was settled by people from specific parts of England. Similar things happened in the Spanish-speaking world, for example people from Andalusia to Mexico, people from the Canaries to the Caribbean.
[3] This was actually the second time Pennsylvanians fought with another colony or state. Suck it, Cresap.
[4] I suspect we don't talk as much about New York during the Revolution as we do Philadelphia and Boston because we mostly got our asses kicked there. The British abandoned Boston early in the war, Philly was occupied only after a fight but both the Declaration and Constitution were written there, and the interior was never occupied, with the pesky insurgents brazenly camping right up the Schuylkill in Valley Forge.
[5] The roundabout language of "culturally ancestral" disqualifies St. Augustine, Roanoke, along with Cahokia and every Native American city, since there isn't an unbroken cultural chain from any of them to us today in modern America.
[6] There's a great statistic cited in Zakaria's Post-American World that I will give in the abstract here, to maximize impact. Country 1 has a sound lead in industry X; Country 2 in industry Y. Sales in industry X are at least an order of magnitude bigger than Y. So you want to be Country 1 right? Filling in the blanks: the year was 1900, Country 1 was the UK, industry X was bicycles, Country 2 was the US, and industry Y was automobiles. Extending this to Virginia (and the South in general), its better climate made it over-reliant on agriculture, and the industrial revolution arrived late and weakly.