Meet the original House of the Rising Sun
Welcome to Japan, Nippon-Koku, the "Land of Sun's Origin", hence, the Land of the Rising Sun. This archipelago of over 6000 islands, has a population of roughly a 130 million people all wedged into a total land mass the size of Montana.
And you thought your city was crowded
This is one of the oldest continuously populated regions in the world, with early civilizations stretching back 30,000 years, and modern settlements in existence for the past 15,000. So, like most eastern societies, Japan takes the long view on life (unlike the West where we think our 230 year old constitution is big shit).
This tree is older than the British Monarchy, four times older than the U.S. Constitution, as old as Christianity and yet is still only 1/5th as young as China.
Also, like China, Japan went through several fractured manarchies, until unification in 740, with the Nara state. However, it is under the shogunate and feudal era, which began in 1185 for which Japan's history is best known, and the rise of the Samurai. For almost four hundred years, Samurai raided into China and Korea until Eurpoeans discovered the Pacific Gem.
Samurai > Ninja
After another two hundred years of trade, the Japanese went into seclusion...until America's Comodore Perry literally forced Japan to open its doors to Americans and American trade in 1854 (can't imagine why that would have pissed them off). The rest thereafter you know, hereditary divine kings, continual raids into China and Korea, Pearl Harbor, Midway, WWII, and all of that messiness culminating in an abominable war crime.
This is what you would have seen had you been sitting on your Nagasaki terrace, having tea, on August 9th 1945. It would have been the last thing you saw before you were evaporated in heat three times the temperature of the sun's surface. They were actually the lucky ones. Sidenote: WTF? Did we really do this?
But, bygones being bygones and such, Japan has emerged as an ally of Western democracies, and invaluable trade partner. However, it should be noted, that by "partner" we really mean passive-agressive nemesis with far greater educational and manufacturing supremacy than fat, lazy europeans and americans. Today, Japan has a complex representative democracy, and they will gladly take your money, but don't even think about moving there: You really aren't wanted, I promise.
Thank you for visiting, shouldn't you really be pissing off now?
Also, much is made of the pacifist constitution forced on Japan; however, "pacifist" in this context" is similar to "trade partner", as Japan has a standing army of just under 300,000 people with another 22 million available for immediate call-up if needed for peace-keeping. And, as is well-known, the most powerful arsenal in Japan's military is their mecha-men, cyborgs, conjoined robots, and other battle-bots.
The Japanese will see your Navy SEALS and raise you a Voltron
Alas, it's not all fun and games in Japan these days: The Pacific Rim bubble and Tech bubble crashes of '98 and '99 really did a number on the Japanese economy. Also, as you would expect for a nation with almost no natural resources, they are heavily dependent on outside trade for the valuable goods to make their economy (2nd most productive, 3rd largest) really hum. Of greater importance is that Japan, normally a rice-heavy society, has begun to import great quantities of food, with almost 60% of their food now being imported. A potential Malthusian nightmare awaits. Finally, Japan still hunts whales for purely social reasons, and nothing can get them to realize the ecological damage that they are doing, and that makes this facet of their society fucked.