Let's do something different. Instead of wanking nations into globe-spanning empires or socialist/libertarian/Social Credit/whatever utopias, let's do the same with places a bit closer to home. The towns, cities, states, provinces, prefectures, etc. that we grew up in.
To start, I'll use my home state, New Jersey, as an example. Note that, while this thread is in the Pre-1900 section, PODs from any time are accepted. I just put it there because my POD is before 1900.
----------
The Garden of Eden: The History of New Jersey, 1860-Present
The POD is a Confederate victory in the American Civil War. The campaign in the West goes much less smoothly for the Union, and with fewer victories to show for it, war weariness is stronger than in OTL. In 1864, George B. McClellan is elected US President on a platform of making peace with the Confederacy, which he does. (The exact details of who gets what aren't that important for the purposes of the timeline, but for those interested, the Confederacy gets western Kentucky, the Ozark region of Missouri, the Indian Territory, and the Arizona Territory, in addition to all eleven Confederate states.) America quickly realizes that having the national capital on a border with a nation that they had just gone to war with isn't a good long-term strategy, so it is decided that the capital is to be moved. McClellan, being from New Jersey, recommends Trenton as the new capital, and gets his way. Trenton, New Jersey (or, as it is soon known, Trenton DC) becomes the new capital of the United States, with the state government moving to New Brunswick.
In the 1890s, Thomas Edison opens his Black Maria studio in West Orange, establishing the American motion picture industry. As the movies take off, other filmmakers set up shop in New Jersey. Edison, being the greedy little bastard that he is, creates the Motion Picture Production Company in 1908 to monopolize the early film industry and drive his competitors out of business. (All this happened in OTL.) In response, the out-of-work filmmakers head on over to Trenton DC to petition the President, famed trust-buster Teddy Roosevelt, to do something about Edison's monopoly. The MPPC trust is broken up in 1910, five years ahead of OTL, meaning that fewer filmmakers flee the state of New Jersey for locales like California (which they did to escape the reach of Edison's lawyers). By 1930, New Jersey has emerged as the largest film production center in the world, with the little burg of Hollywood, California a distant second. The creation of the Motion Picture Production Code in 1933, however, causes a number of filmmakers to head west in order to make movies free of studio censorship. For the rest of the century, the studios in New Jersey and the so-called "rebel" studios in Hollywood (which followed a far more lenient version of the Production Code) would compete for the American moviegoing public's dollars.
The '40s and '50s mark the birth of American suburbia. New Jersey, with the cities of New York, Trenton DC, Asbury Park (TTL's Hollywood) and Philadelphia all in close proximity, becomes the epicenter of the suburban explosion. By 1970, New Jersey's population has surpassed eight million, and is on track to reach ten million by the end of the century. In addition, since much of the OTL Sun Belt region is a part of the Confederacy here, the boom is instead directed into the western United States, with military and technological installations proliferating there instead of in the South. (The CDC, for instance, is based in Denver rather than Atlanta, Edwards AFB becomes NASA's chief launch site instead of Cape Canaveral, and Houston's biotech boom is instead focused on Oakland, California.) Anybody well-versed in the geography of the region should know that this will not end well. In the '70s, many western states' water supplies quickly start straining under the weight of these boom towns. The looming crisis comes to a head in 1982, a year that sees the rationing of water in several western cities. This leads to rioting in Billings, Flagstaff and especially Las Vegas, where angry looters target the casinos on the Strip due to the fact that, while suburbanites were seeing their water use heavily curtailed, the casinos were able to keep running their extravagant fountains and pools without similar restrictions (mainly because the Clark County government was in the casinos' pocket). The "Great Migration," as the boom of the western US was known, comes to a halt virtually overnight as scenes of suburban chaos are splattered on TV screens around the world. Without new arrivals coming in, construction, real estate and related industries collapse, throwing the western US into an economic tailspin. This means that the out-migration from the East Coast (including New Jersey) and the Midwest ends decades earlier than in OTL.
By 2010, New Jersey's population stands at nearly eleven million people. As the heart of America's political and cultural nexus, the Garden State is one of the wealthiest regions on the planet. With this prosperity, however, comes severe overcrowding, as well as all the environmental issues that come with it. Due to heavy pressure on water supplies and not wanting to face the same situation as the western US, the government in New Brunswick has passed some of the strongest environmental laws in the nation, placing extremely tough restrictions on development in the Highlands region in the northwest of the state (which is critical to New Jersey's water supply). As a result, while the state as a whole has even more urban sprawl than in OTL, the Highlands of Morris, Warren, northern Passaic and Sussex Counties have been more protected from development, butterflying away "edge cities" like Parsippany and keeping the area a mix of small-to-medium-sized towns surrounded by farms and forests. New Jersey's environmentalism has reached into other areas too. With the New Jersey State Thruway system (OTL's New Jersey Turnpike and Garden State Parkway) and the Capital Beltway all cluttered with hellish traffic jams nearly nonstop, the NJTransit rail system has seen far more investment than in OTL, reaching nearly every community of over 25,000 within the state. In 1988, New Jersey became the first state in the nation to take action on reducing its carbon footprint. And with the motion picture capital of Asbury Park located on the Jersey Shore, there's no shortage of big-name actors to champion environmental causes within the state.