Useful Notes / The Forty Seven Prefectures

Contrary to popular belief, Japan is not only Tokyo. There are 46 other prefectures that the country is divided into, which are in turn (for the most part) divided further into cities and districts; districts are further subdivided into towns and villages. Prefectures are largely dependent on the national government in Tokyo for financial support and their organization is defined by the Local Autonomy Law, which went into effect in 1947. Prefectures, however, elect their own governors and do get some autonomy in their policy-making. If you're familiar with how the American government is set up, an oft-used analogy is the relationship between the county and the state it's part of.

The current prefectural system was developed out of the Meiji Restoration in 1868; prior to that Japan was divided into provinces, which weren't legally the fiefdoms the local daimyo ruled over as feudal lords but for administrative purposes ended up as the same thing. Technically, the provinces of Japan were never abolished (what was abolished was the -han fiefdom system that the local daimyo actually ruled, which ran concurrent to the provinces - the current prefectures came from a couple rounds of consolidating some 300 han) but nowadays are chiefly used for local-branding purposes. There's a good deal of overlap between the boundaries in both systems, though - if you compare a map of Japan's feudal provinces with a map of its modern prefectures, their borders don't deviate all that much from each other (the big exception is the Tohoku region, where two provinces are now six prefectures).

A note about titles - there's not one single title used in Japanese for all 47 of them. The Western standard of calling Japan's subdivisions "prefectures" is from Portuguese contact in the 15th Century, who called the fiefdoms ruled by the various daimyo prefeitura. Japan currently has four different designations for its first-level political subdivisions, the titles borrowed from Imperial Chinese administration organization. After the Meiji Restoration each type of prefecture had their own set of administrative powers, though since World War II the differences have largely become inconsequential:

  • Tokyo is a -to (都). Tōkyō-to is usually translated as "Tokyo Metropolis", reflecting the fact that it has grown even higher than its erstwhile peers in Osaka and Kyoto in terms of importance.
  • Hokkaido is a -"dō" (道), which translates as "circuit". It is a remainder from the Asuka (no, not that one) Period (538-710 AD), when Japan was divided into Gokishichidō: five provinces centered around the Imperial capital Nara and later Kyoto (Kinai), and seven circuits based on the roads that connected them to those five central provinces. (Hokkaido was not one of those original seven circuits - it's basically a - because the Meiji Government didn't know what else to call it as it wasn't developed enough to be a -ken.)
  • Osaka and Kyoto Prefectures are titled with -fu (府). In Imperial China, it implied the subdivision in question was an urban center of national importance - given that for most of Japanese history Kyoto was where the Emperor resided and Osaka was the largest trading center in the country (especially for rice), it seems justified. After the Meiji Restoration Tokyo was also a -fu until the national government made it a -to in 1943 in order to retain more control over the largest urban area in the country when World War II was turning against them.
  • The other 43 prefectures are officially called -ken (県). Prefectures being styled with this implies that the prefecture is a more rural area.

All 47 prefectural governments are sometimes collectively referred to as to-dō-fu-ken (都道府県).

Prefectures are organized by regionnote  and are numbered in order of ISO ordering. Listed populations are estimates as of October 1, 2011.


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    Hokkaido (北海道) 

1. Hokkaido (北海道)
Capital: Sapporo (札幌)
Other cities of note: Asahikawa (旭川), Hakodate (函館)
Population: 5,485,952 (8th)

Literally translates as "Northern Sea Circuit". Hokkaido is physically the northernmost of the four main islands. As mentioned above, the "-do" indicates the type of prefecture it is, so "Hokkaido Prefecture" is technically redundant unless you want to distinguish between the island and the political entity. The prefecture also includes several small islands around it (including, officially, four that were seized by the Soviet Union at the end of World War II and are a major reason why Japan and Russia do not currently have a formal peace treaty). Due to its late development and relatively large size with many sparsely-populated areas, rather than cities and districts Hokkaido is subdivided into subprefectures which handle the local administrative work.

Historically called Ezo (蝦夷)note , the island was for most of its history inhabited by Ainu - the cold, snowy winters discouraged large-scale Japanese settlement beyond the southern tip through most of Feudal Japan's history, and for the most part whatever shogunate was in power was content to let the Matsumae clan have feudal domain over the Ainu and retain a monopoly on trade with them. It wasn't until after Commodore Perry's black ships arrived and the shogunate began modernization efforts did control of Hokkaido tighten, mainly to stop the Russians from taking it for themselves for their own Far East expansion.

Hakodate was the Last Stand of the Tokugawa Shogunate in the Boshin War following the Meiji Restoration in 1868 - a bunch of shogunate loyalists took over the fort there and held out until they were crushed the following May. The Meiji government took up the task of developing Hokkaido and brought in help from American advisers - the effects can be seen today in much of Hokkaido's historical architecture, which look more like something you'd see in the American Midwest, and the Western grid-pattern street layout of Sapporo. The only other Japanese cities to have such a layout are Kyoto and Nara (they got that pattern because of Chinese feng shui); pretty much every other city in Japan has streets that cross and meet each other at irregular angles, mainly to confuse rival daimyo who might try to take over their turf.

Being settled very late by Japanese immigrants, Hokkaido arguably has the least distinctive culture among all regions of Japan, further supported by the fact that those immigrants mainly came from the Kanto region with minorities from other regions that got quickly assimilated, so the people here speak generic Japanese, i.e. the Tokyo dialect. This means that despite symbolizing a perfect Grim Up North (Truth in Television, as the entire island is guaranteed to be blanketed with snow during winter), Japan's actual Grim Up North is Tohoku, just right across the Tsugaru Strait, while Hokkaido is mainly used as a setting of refuge, not strangeland.

Today, it's probably most well-known for its tourism opportunities, whether it's being able to escape the monsoon rains that drench the rest of Japan in the humid months of June and July, or the skiing opportunities in the winter (Sapporo hosted the 1972 Winter Olympics), or the many hot springs and natural landmarks all over the island. It's also known for its diverse array of agricultural products - Hokkaido has about a quarter of all the arable land in Japan. Since 1988, activity has been spurred with the presence of Seikan Tunnel, the longest tunnel with an undersea segment in the world, which connects Hokkaido with Honshu.

    Tōhoku (東北) 

In the northeastern part of Honshū, north of the Kanto Plain lies the Tohoku Region; "Tōhoku" literally translates as "east-north". Historically this is a less-developed region, as it was settled by Japanese centuries after the center of its civilization developed to the south. The mountainous geography of the area, the rather harsh winters, and the relative lack of easy transport access (by road or by sea - the rivers generally aren't suitable for boats and there aren't many decent harbors) further slowed settlement. Despite the relatively short growing season, the region is now known as an agricultural center, as a disproportionate amount of the nation's rice is grown here since similar populated areas in the south went for industrialization first. This combination of factors is likely why someone with a Tohoku Regional Accent (which sounds like the speaker is having a very bad cold) gets stereotyped as a backwoods hillbilly, and the reason why it's known as the Grim Up North of the archipelago (even after Hokkaido is settled extensively). Just count how many times a media is basing their environment from the Ghibli Hills of Aomori and Akita, which looks like something you see from My Neighbor Totoro.

During the age of the Shogun, this whole region of six current prefectures was made up of just two provinces (Dewa and Mutsu) because of its relative lack of development, and the comparitive remoteness from the rest of Japanese civilization meant the local clans (most notably the Date family, who in exchange for keeping the Ainu at bay in Hokkaido were exempt from both rice tribute and the sankin kotai policynote  under the Tokugawa shogunate) always maintained some distance and autonomy from the center of power in Kyoto or Edo.

This is the region that was devastated the most by the March 2011 earthquake and ensuing tsunami and nuclear reactor meltdown - the epicenter of the earthquake was about 72 kilometersnote  off the coast of Miyagi Prefecture.

2. Aomori (青森)
Capital: Aomori
Population: 1,362,820 (31st)

The northernmost prefecture of Honshu.

3. Iwate (岩手)
Capital: Morioka (盛岡)
Population: 1,314,076 (32nd)

The Kosode Coast in Kuji city is best known as the filming location for Sodegahama in Amachan, a popular TV drama that explores the region's sea urchin-diving industry.

4. Miyagi (宮城)
Capital: Sendai (仙台)
Population: 2,326,735 (15th)

Most populous and developed of Tohoku prefectures, it was where the (in)famous One-Eyed Dragon Date Masamune has set his shop after Sekigahara, founding his capital of Sendai in 1600. Masamune was a patron of culture and education, and his legacy continues to this day — Tohoku University in Sendai was one of thirteen Imperial Universities founded fter the Meiji Restration, and is a stronghold of engineering and materials sciences: to this day it is a heart of Japanese metallurgical science, while the famous Yagi-Uda antenna (used in radars and TV receivers) was invented there in The Thirties, and the first practical blue LED in The '90s. To this days Sendai remains more of an university city than anything, while its suburb of Matsushima, with its bay dotted by the picturesque pine-overgrown islets, was considered one of the three best views of Japan — to the extent that even the legendary Basho was at loss of words for its beauty. Unfortunately, it was the area hardest hit by the 2011 earthquake and tsunami.

5. Akita (秋田)
Capital: Akita
Popualtion: 1,074,858 (38th)

6. Yamagata (山形)
Capital: Yamagata
Population: 1,161,214 (35th)

7. Fukushima (福島)
Capital: Fukushima
Population: 1,989,834 (20th)

Home of the unfortunate nuclear plant.

    Kantō (関東) 

"Kanto" literally translates as "East of the Barrier" - the "Barrier" in question was the Hakone (箱根) Checkpoint, a town located at the very western edge of present-day Kanagawa Prefecture and marked the point at which Tokugawa Shogunate officials would stop and check travelers from points west in order to enforce restrictions on the movement of women and weapons. The area itself has the Kanto Plain, which makes up about half the region and is the single largest plain in Japan. The plain is fed by many rivers that flow through it - this combined with the fact that arable land is at premium in a country that is 90% mountain made it a very lucrative location for Tokugawa Ieyasu to establish his center of power in 1603.

The Kanto region was the heart of feudal Japan's power during the Kamakura Period (1185-1333), partly thanks to the resident Hojo clan who helped the Minamoto clan establish a shogunate over the rest of Japan and later seized control of the shogunate with some slick backroom politics. It was divided into eight provinces: Shimotsuke, Hitachi, Kozuke, Musashi, Kazusa, Shimosa, Awa, and Sagami. In the Sengoku Jidai, an unrelated line of daimyo took the Hojo name and seized power in the region, ruling from Odawara. Kanto became the seat of shogunate power again during the Edo Period (1603-1867), remaining so after the Meiji Restoration with the Emperor physically moving from Kyoto to the now-renamed Tokyo. Tokyo and Yokohama were major industrial centers that attracted large numbers of migrants, even with the Great Kanto Earthquake of 1923 resulting in over 100,000 dead.

With about 1/3 of Japan's entire population (and Tokyo's metropolitan area still growing in a country whose national population is starting to decline), as well as the modern center of the nation's politics, business, and culture, this will most certainly remain the most prominent region of Japan for the foreseeable future.

8. Ibaraki (茨城)
Capital: Mito (水戸)
Population: 2,957,706 (11th)

Historically known as Hitachi Province. Yes, as in the Hitachi company that might have made your TV or air conditioner - the company was founded in the namesake town located in the prefecture in 1910.

9. Tochigi (栃木)
Capital: Utsunomiya (宇都宮)
Population: 2,000,010 (19th)

10. Gunma (群馬)
Capital: Maebashi (前橋)
Population: 2,000,514 (18th)

11. Saitama (埼玉)
Capital: Saitama (さいたま)
Population: 7,207,139 (5th)

If Tokyo is New York, Saitama is New Jersey minus the petrochemical refineries (they're more to the south and east in Chiba and Kanagawa).

12. Chiba (千葉)
Capital: Chiba
Population: 6,214,148 (6th)

13. Tokyo (東京)
Capital: Shinjuku (新宿)
Population: 13,195,974 (1st)

See the Useful Notes page for more detail about the 23 special wards you're probably looking for. Note however, that Tokyo is not just the 23 special wards; there're the oft-forgotten Tama Area to the west, which is much larger but is largely rural (yes, Tokyo does have farms) or semi-urban and serve as bedroom communities, and the Izu and Ogasawara Islands that stretch far south into the Pacific Ocean, the latter of which includes Iwo-to (misread as Iwo Jima), where the famous photograph of six US Marines raising the American flag took place. Compare the situation between New York City and New York State.

14. Kanagawa (神奈川)
Capital: Yokohama (横浜)
Population: 9,058,094 (2nd)

Although long ago absorbed into the Tokyo metropolitan region, Yokohama remains a separately incorporated city (a category which technically excludes Tokyo) and thus is classified as the second-largest city and the largest proper city in Japan. During the Sengoku Jidai, the city of Odawara to the southwest of Yokohama was the seat of the Hojo clan, until it was overtaken by Toyotomi Hideyoshi in 1590. The Port of Yokohama was established in 1859 after Commodore Matthew Perry forced Japan to allow foreign trade; it eventually overtook Kobe to become the busiest port in Japan and one of the busiest ports in the world.

    Chūbu (中部) 

"Chubu" literally translates to "The Central Portion". This is a fairly diverse group of prefectures encompassing the general area between the Kanto and Kansai regions. It's often subdivided into three subregions:

Hokuriku (北陸地)

These four prefectures lie on the coast of the Sea of Japan. During the shogun period, seven provinces existed in their place: Noto, Etchu, Kaga, Echizen, Wakasa, Echigo, and Sado provinces. During the winter air from Siberia picks up moisture traveling across the Sea of Japan before it is forced upward by the Japanese Alps and causing it to dump its precipitation, making this area among the snowiest places on Earth.

15. Niigata (新潟)
Capital: Niigata
Population: 2,362,158 (14th)

Its most famous historical figure is most likely Uesugi Kenshin, whose base of power was here. Niigata also includes Sado Island off its western coast, which formerly formed its own province and used to banish people who have committed so great an infamy but not enough to be given a death penalty.

16. Toyama (富山)
Capital: Toyama
Population: 1,087,745 (37th)

Formerly known as Etchu province, its mountain villages were mainly specialized in silk production — the remains of which can still be seen in the UNESCO World Heritage village of Gokayama, — while the coastal areas specialized in fishing. Nowadays it's more known for energy production, being the site of the tallest and most picturesque hydro power station in Japan — the Kurobe dam on the eponymous river, and for P. A. Works, which is headquartered in the city of Nanto. Tateyama-Kurobe Alpine Route is a picturesque road that goes through the deepest nooks of Japanese Alps, which are said to be the snowiest place on the Earth: a particular attraction is a cut in the snowdrifts over the road, which is made every spring — the walls of compessed snow sometimes reach the height of 15 meters.

17. Ishikawa (石川)
Capital: Kanazawa (金沢)
Population: 1,166,309 (34th)

18. Fukui (福井)
Capital: Fukui
Population: 802,906 (43rd)

Kōshin'etsu (甲信)

This region encompasses the most mountainous parts of the Japanese Alps, and most of its population is concentrated in basins scattered throughout. Historically the area was known for its silk production; nowadays more of its population is involve in light manufacturing. Provinces that once existed in the area include Kai and Shinano.

Niigata is sometimes included in this group.

19. Yamanashi (山梨)
Capital: Kōfu (甲府)
Population: 857,459 (41st)

Directly to the west of Tokyo, Yamanashi includes the northern slopes of Mount Fuji. Historically known as Kai Province, home of the Takeda clan.

20. Nagano (長野)
Capital: Nagano
Population: 2,142,167 (16th)

The 1998 Winter Olympics were held here.

Gifu

21. Gifu (岐阜)
Capital: Gifu
Population: 2,070,908 (17th)

Gifu Prefecture itself is usually not considered a part of any of the three subregions listed on this page. When it does get classified it's often split, with its mountainous northern half (formerly Hida Province) going to the Kōshin'etsu region and the southern plain near Nagoya (formerly Mino Province) grouped into the Tōkai region. The namesake town's central location near the main routes to and from Kyoto made it a key strategic point during the Sengoku Jidai - as the saying goes, "control Gifu and you control Japan." Sekigahara, the site of the most famous battle in Japanese history, lies on the Tōkaidō Road near the prefecture's mountainous western boundary.

Tōkai (東海)

The name itself means "east sea", and refers to one of the seven circuits of the Gokishichidō - the Tōkaidō region stretched from the Kansai Plain and ran along the Pacific coast all the way to present-day Ibaraki Prefecture. The Tōkaidō Road, meanwhile, was the road that the Hakone Checkpoint (see the Kanto region) sat on, being the most important road of the Edo Period and today is still the most heavily travelled route in Japan thanks to all the industry that it served by it.

Former provinces of the region are Izu, Suruga, Totomi, Mikawa, and Owari.

Mie Prefecture (listed here under Kansai) and the southern half of Gifu Prefecture are often considered part of this subregion. The Chūkyō (中京) Metropolitan Area (Shizuoka, Aichi, and Mie) centered around Nagoya are especially close economically.

22. Shizuoka (静岡)
Capital: Shizuoka
Population: 3,749,274 (10th)

Includes the southern slopes of Mount Fuji as well as the hilly Izu Peninsula, popular for its hot springs.

23. Aichi (愛知)
Capital: Nagoya (名古屋)
Population: 7,416,336 (4th)

Historically divided into two provinces, Owari in the north and Mikawa in the south. Oda Nobunaga and Toyotomi Hideyoshi were both from Owari (hence why the former was, pre-ascendancy, known as the Fool of Owari), while Okazaki in Mikawa was Tokugawa Ieyasu's ancestral home.

    Kansai (関西) 
"West of the Barrier", though the barrier in this case was the Osaka Tollgate on the border of present-day Kyoto and Shiga Prefectures. This is the historical center of Japanese civilization and today remains the biggest counterpart to Tokyo and the Kanto region. The Kinki (近畿) region is more or less synonymous with Kansai, though it generally excludes Mie. Provinces that used to exist in the area are Ise, Shima, Kii, Yamato, Izumi, Kawachi, Yamashiro, Omi, Wakasa, Tango, Tamba, Settsu, Harima, Tajima, Awaji, and Iga.

Before the Edo period, the Kansai Regional Accent was the prestige dialect of Japan, as it was the speech of the royal family and the shogunate. Even today, the Kyoto variant still retains much of its splendor, being regarded as posh and soft-sounding compared to other variants.

24. Mie (三重)
Capital: Tsu (津)
Population: 1,847,223 (22nd)

Location of the Ise Grand Shrine, one of (if not the most) sacred shrines in Shinto.

25. Shiga (滋賀)
Capital: Ōtsu (大津)
Population: 1,413,513 (28th)

Centered around Lake Biwa, the largest inland body of water in Japan. Formerly rotten with industrial production, currently rotten with decaying factories. Fittingly, it has a sister-jurisdiction relationship with Michigan (which is of course defined by the largest lakes in the US and decaying industry). Otsu was also a place where the Russian Crown Prince Nicolas (later to be Tsar Nicolas II) was attacked by a deranged policeman, which indirectly caused Russo-Japanese War couple of decades later.note 

26. Kyoto (京都)
Capital: Kyoto
Population: 2,631,671 (13th)

The Kyoto Basin, also known as the Yamashiro Basin after its previous provincial name, constitutes the historical heart of Japan. The basin is defined by the Katsura, Kamo, Uji and Kizu Rivers, which descend into the plain from their sources in the surrounding mountain (or, in the case of the Uji, the Seta outlet of Lake Biwa) and merge together to form the Yodo River that flows into the sea at Osaka. The town of Uji, where the old road between Kyoto and Nara crosses the river of the same name, was significant during the Heian period as a summer retreat and burial ground for the Fujiwara clan. The last part of The Tale of Genji are set here. Uji was the site of two major battles during the Genpei War. Today, Uji is known for old temples, green tea and Kyoto Animation. Two rural provinces, Tanba and Tango, also became part of Kyoto Prefecture, adding little more than vast expanses of rural territory and access to the Sea of Japan.

Kyoto City has the most number of heritage sites of any city in Japan, thanks to being an imperial capital for so long and being spared from the worst bits of World War II (it was briefly considered a planned site for the atomic bombing project, but the Secretary of War rejected it on account of his fond memories of honeymooning in the Old City).

As noted above, the Kyoto variant of the Kansai Regional Accent is something of an anomaly, being known for its soft and feminine-sounding pronunciation in an area known for their harsh and clipped speech pattern.

27. Osaka (大阪)
Capital: Osaka
Population: 8,861,012 (3rd)

Osaka City is the third largest city in Japan and considered the capital of Western Japan and an antithesis to Tokyo. Don't try to bring up Tokyo here, Osakans are proud of their heritage and rightly so; it was for the longest time the center of Japan, being located close enough to the sea giving it easy access to foreign trade, close enough to Nara and/or Kyoto to receive their continuous patronage, and close enough to Ise to receive moral support. Any merchant who wanted to stop over to Japan had to land on Osaka, and it soon became the definition of cosmopolitan in the eyes of many Japanese during the Middle Ages.

Call someone from here an idiot at your own risk.

28. Hyogo (兵庫)
Capital: Kobe (神戸)
Population: 5,581,968 (7th)

The prefecture includes the Awaji island, located in the Seto Inland Sea. Japanese mythology considered it to be the first of the archipelago to form. It was formerly a separate province, but was merged with Hyogo after the Meiji Restoration. Unusual for non-Home Islands, it's very urbanized, thanks to direct connection with Honshu through the Akashi-Kaikyo Bridge, the longest suspension bridge in the world.

29. Nara (奈良)
Capital: Nara
Population: 1,395,845 (30th)

Founded in 710, Nara is Japan's oldest city.

30. Wakayama (和歌山)
Capital: Wakayama
Population: 995,010 (39th)

    Chūgoku (中国) 

Though the name "Chūgoku" literally means mid-country, the region occupies the western part of Honshu as an Artifact Title from when the center of Japanese civilization was between Kyushu and the Kansai Plain, which would put this region in the middle. The region can be split in half down its mountainous middle, with the San'in (山陰) region bordering the Sea of Japan and the San'yō (山陽) region bordering the Inland Sea. (Portions of Hyogo and Kyoto prefectures were historically also part of the San'in and San'yō regions.) Since "Chūgoku" is also used to refer to China since No More Emperors, tourist agencies often use the term "San’in‐San’yō region" to distinguish between them.

There are 11 provinces that used to exist in this region: Inaba, Hoki, Izumo, Iwami, Nagato, Suo, Aki, Bingo, Mimasaka, Bizen, and Bitchu.

31. Tottori (鳥取)
Capital: Tottori
Population: 585,494 (47th)

Formerly known as Inaba province, it's deeply connected to the oldest legends of Japan. Similarly to the nearby Shimane prefecture, it features heavily in the myths of Okuninushi, a legendary ruler of the land who yielded it to the first Emperor of Japan, and is a home of his trusty sidekick, White Hare of Inaba (who is venerated in a small shrine in Tottori city). Sakaiminato, a small fishing port in the prefecture, is famous for its Eshima Ohashi bridge over the Lake Nakaumi — "the scariest bridge in the world" due to it being exceptionally steep. The prefecture also features the only genuine sand dune in the country, which is a significant tourist trap as of itself.

32. Shimane (島根)
Capital: Matsue (松江)
Population: 712,292 (46th)

The eastern part of the prefecture, on what used to be Izumo Province, is the Japanese equivalent of Jerusalem (while Ise is the equivalent of Vatican City), featuring many Shinto pilgrimage sites and other sacred spots. It was the capital of mythological Japan, ruled by Okuninushi, an ancestor of the legendary founder of the Japanese imperial family. It is also the location of Yomotsu Hirasaka, believed to be the main entrance to The Underworld.

The province officially includes the Liancourt Rocks, which are disputed with and de facto administered by South Korea.

33. Okayama (岡山)
Capital: Okayama
Population: 1,940,559 (21st)

34. Hiroshima (広島)
Capital: Hiroshima
Population: 2,855,045 (12th)

The castle town was founded in 1589 by Mori Terumoto, one of the main opponents of Toyotomi Hideyoshi during the latter's drive to unite the provinces of Japan during the Sengoku Jidai. It grew in prominence after the Meiji Restoration when it became a big industrial and transportation center (as the westernmost large city on Honshu with a good harbor). Nowadays it's known for its version of okonomiyaki (the ingredients are usually layered; the more broadly-known Kansai version mixes the ingredients together while cooking) and its high number of street cars.

And, yes, it was the target of the first atomic bomb dropped by the United States on August 6, 1945.

35. Yamaguchi (山口)
Capital: Yamaguchi
Population: 1,442,428 (25th)

The prefecture contains Shimonoseki, which other than hosting one end of Kanmon Bridge connecting Honshu with Kyushu, is also the location for the signing of treaty between Imperial Japan and Qing China ending the First Sino-Japanese War.

    Shikoku (四国) 

The smallest of Japan's four main islands. It's Exactly What It Says on the Tin, as the name translates as "Four Provinces". The four prefectures that currently make up the island are pretty much direct descendants of four provinces from Japan's feudal days: Awa, Sanuki, Tosa, and Iyo. Home to the 88 Temple Pilgrimage and a bunch of rice fields.

36. Tokushima (徳島)
Capital: Tokushima
Population: 780,236 (44th)

Formerly known as Awa Province. The prefecture is the location of one end of the Onaruto Bridge, the first bridge to connect Shikoku with Honshu. Most famous for the annual Awa Odori dance festival in August. Also notable for the wild Naruto whirlpools, named after a nearby city, which inspired quite a lot of paintings and even a topping for ramen. And the famous fictional ninja.

37. Kagawa (香川)
Capital: Takamatsu (高松)
Population: 991,947 (40th)

Birthplace of Kobo Daishi, polymath and founder of Esoteric Buddhism. Also known for Sanuki Udon noodles, named after the old title of the province. The city of Sakaide is one end of the Seto-Chuo Expressway, the second bridge to connect Shikoku with Honshu.

38. Ehime (愛媛)
Capital: Matsuyama (松山)
Population: 1,423,406 (26th)

The liveliest of the four prefectures, which still isn't saying much. Formerly known as Iyo Province. Home to Dogo Onsen, one of Japan's oldest hot springs and now a fun tourist trap. The city of Imabari is also one end of the Nishiseto Expressway, the third and most complicated of the bridges connecting Shikoku with Honshu (it passes through at least six islands before reaching Onomichi in Hiroshima Prefecture).

39. Kōchi (高知)
Capital: Kōchi
Population: 758,469 (45th)

Has a reputation as Japan's hardest drinking prefecture. Known as Tosa Province back in the day. Birthplace of samurai/politician/negotiator/revolutionary/reformer Ryoma Sakamoto, commonly known as "that ronin from Tosa" during his lifeltime.

    Kyushu (九州) 

A bit of an Artifact Title - though there are only seven prefectures on here and the surrounding islands, the name translates as "Nine Provinces" as there used to be, well, nine provinces (Chikuzen, Buzen, Bungo, Hizen, Chikugo, Higo, Hyuga, Osumi, and Satsuma) on the island in the country's feudal days. The nine however doesn't include the Tsushima Islands, located off the western coast, which were administered as a separate province of the same name (today, it's part of Nagasaki Prefecture).

The Japanese accents of the island (Kagoshima, in particular) are notable for being very divergent from Standard Japanese to the point of mutual unintelligibility. They are not classified in the dualism of Western and Eastern Japanese and instead form their own branch.

40. Fukuoka (福岡)
Capital: Fukuoka
Population: 5,079,291 (9th)

41. Saga (佐賀)
Capital: Saga
Population: 846,787 (42nd)

42. Nagasaki (長崎)
Capital: Nagasaki
Population: 1,417,423 (27th)

The historical center of nanban (European)note  trade with Japan, dating back to the 16th Century first with the Portuguese and then later with the Dutch. During Tokugawa rule the closing off of the country to outside influence effectively sealed off official contact with the West everywhere except for highly-regulated contact at Dejima, an artificial island in Nagasaki's bay (which was originally a small peninsula - the island was made by digging out a canal that cut across it). Thanks to this early and extensive European influence, Nagasaki consistently ranks as the most Christian prefecture of Japan; if a media features Christian characters or otherwise set in a place that's unusually Christian (e.g. Sakamichi no Apollon), chances are it's set somewhere here.

The city became the target of the Fat Man atomic bomb dropped by the United States on August 9, 1945, making it the second and last (hopefully) city to be destroyed by an atomic bomb.

43. Kumamoto (熊本)
Capital: Kumamoto
Population: 1,812,575 (23rd)

44. Oita (大分)
Capital: Oita
Population: 1,191,430 (33rd)

45. Miyazaki (宮崎)
Capital: Miyazaki
Population: 1,130,983 (36th)

46. Kagoshima (鹿児島)
Capital: Kagoshima
Population: 1,698,695 (24th)

A wide variety of foods are grown and raised here. Also a major center of activity for JAXA, Japan's space agency, as the main launching facility at Tanegashima is in this prefecture.

This prefecture also includes some islands of the Ryukyu island chain, including Yakushima, a UNESCO World Heritage Site famous for its ancient forests.

    Ryūkyū Islands (琉球諸島) 

The Ryūkyū islands were once disjointed island states that had quite a history with both China and Japan. Where it was situated was a strategic location for trade routes and unlike Japan, the Ryūkyū people welcomed foreigners. For most of the Middle Ages, they had little contact with Japan and instead usually traded with China. By the early 1400s, the clans united to form the Ryūkyū Kingdom. In the early 1600, the Shimazu Tadatsu of Satsuma invaded the islands. Rather than face bloodshed due to the lack of military prowess, the kingdom surrendered and paid tribute to the Japanese Shogunate. By the 1870s during the Meiji Restoration period, they were formally annexed into Japan to be ruled by their government.

Okinawa, the largest island in the chain, played a vital point during World War II, as it was the location for the last major battle in the Pacific front; some historians believe that the long and bloody campaign was a deciding factor for the decision to use atomic bombs. After the war, the islands remained under US occupation until 1972. Now, the islands are popular tourist destination spots and is akin to Hawaii. Okinawa also is home to numerous US military bases, which is still a sore point to this day for the locals.

Scientific studies concluded that the Ryukyu Islanders are more closely related to the Ainu than the Japanese, suggesting that they are descendants of the original inhabitants of the archipelago, the Jomon people (as opposed to the Yamato, the ancestors of most Japanese people). Their languages (Kikai, Amami Oshima, Tokunoshima, Okinoerabu, Yoron, Kunigami, Okinawan, Miyako, Yaeyama, and Yonaguni) are the only living relatives of the Japanese language, though they are not mutually intelligible to it and to each other. However, Japan officially regards the languages as dialects of the Japanese language and are in the position of assimilation to the mainstream (similar to that practiced in France), so the languages are now in various stages of endangerment.

Oh, Karate comes from here, too.

47. Okinawa (沖縄)
Capital: Naha (那覇)
Population: 1,401,066 (29th)

The prefecture includes all islands of the Ryukyu chain south of the 28.5 parallel north (to the north the islands are administered by Kagoshima). The largest city, Naha, dominates the activities of the archipelago and is impressively crowded, urbanized, and metropolitan for a settlement located on a small island with little opportunities for going outward (the northeast part of the Okinawa island is taken up by mountains). Thanks to Naha, the prefecture is well-connected to the Home Islands. Iriomote Island is the second largest island in the prefecture and is mostly national park. The prefecture's Yonaguni Island is the westernmost inhabited island of Japan and is much closer to Taiwan (only 67 miles [107 km]) than it is to Tokyo (over 1200 mi [2000 km]).

Senkaku Islands, currently disputed with both China and Taiwan, are de facto administered by Japan as part of Okinawa Prefecture.
http://tvtropes.org/pmwiki/pmwiki.php/UsefulNotes/TheFortySevenPrefectures