Kamis, 08 Juli 2010

Chinese pyramids

The Chinese pyramids are ancient mausoleums and burial mounds built to house the remains of several emperors of China and their imperial relatives. About 38 of them are located around 25 kilometres (16 mi) - 35 kilometres (22 mi) north-west of Xi'an, on the Qin Chuan Plains in Shaanxi Province. The most famous is the Mausoleum of the First Qin Emperor, northeast of Xi'an and 1.7 km west of where the Terracotta Warriors were found. Chinese pyramids were also built during the Han, Tang, Song, and Western Xia dynasties.
Google Earth clearly shows many of them and includes Panoramio photographs of many. They have flat tops, and thus are more similar in shape to the Teotihuacan pyramids north-east of Mexico City, Mexico than to the pyramids in Giza, Egypt. Although known in the West for at least a century, their existence has been made controversial by sensationalist publicity and the problems of Chinese archaeology in early 20th century.

Recognition in the West


The introduction of pyramids in China to popular attention came in two stages. Many early stories were focused on the existence of "Great White Pyramid." U.S. Army Air Corps pilot James Gaussman is said to have seen a white jewel-topped pyramid during a flight between India and China during World War II. Colonel Maurice Sheahan, Far Eastern director of Trans World Airlines, told an eyewitness account of his encounter with a pyramid in the March 28, 1947 edition of The New York Times. A photo of Sheahan's pyramid appeared in The New York Sunday News on March 30, 1947. This photograph later became attributed to James Gaussman. Chris Maier showed that the pyramid in the photo is the Maoling Mausoleum of Emperor Wu of Han, just outside of Xi'an. Alternative writers such as Hartwig Hausdorf (who speculated it was built by aliens) and Phillip Coppens did much to bring them to public attention.
Despite claims to the contrary, the existence of these pyramid-shaped tomb mounds was known by scientists in the West before the publicity caused by the story in 1947. Shortly after the New York Times story, Science News Letter (now Science News) published a short item saying "The Chinese pyramids of that region are built of mud and dirt and are more like mounds than the pyramids of Egypt, and the region is little travelled. American scientists who have been in the area suggest that the height of 1,000 feet (300 m), more than twice as high as any of the Egyptian pyramids, may have been exaggerated, because most of the Chinese mounds of that area are built relatively low. The location, reported 40 miles (64 km) southwest of Sian, is in an area of great archaeological importance, but few of the pyramids have ever been explored."  Victor Segalen visited China in 1913 and wrote about the First Emperor's tomb (and other mound tombs in the region) in Mission Archeologique en Chine (1914): L'art funeraire a l'epoque des Han.
Some of the pyramids of Xi'an are now tourist attractions and several pyramids have small museums attached to them.

The Development of Mound Tombs in China

 There is a long history of building mounded tombs in China, dating back to at least the Shang-Zhou period.

Partial list of Chinese pyramids



 
 from: http://en.wikipedia.org/wiki/Chinese_pyramids































Selasa, 22 Juni 2010

Takamatsuzuka Tomb

The Takamatsuzuka Tomb (高松塚古墳 Takamatsuzuka Kofun) or "Tall Pine Tree Ancient Burial Mound" in Japanese is an ancient circular tomb in Asuka village, Nara prefecture, Japan.
The tomb is thought to have been built at some time between the end of the 7th century and the beginning of the 8th century. It was accidentally discovered by a local farmer in the 1960s.
The mound of the tomb was built of alternating layers of clay and sand. It is about 16 meters in diameter and 5 meters high. Digging yielded a burial chamber with painted fresco wall paintings of courtiers in Goguryeo-style garb. The paintings are in full color with red, blue, gold, and silver foil representing four male followers and four abigails together with the Azure Dragon, Black Tortoise, White Tiger, and Vermilion Bird groups of stars. The paintings are designated as a national treasure of Japan.
For whom the tomb was built is unknown, but the decorations suggest it is for a member of the Japanese royal family or a high-ranking nobleman. Candidates include:
  1. Prince Osakabe (? - 705), a son of Emperor Temmu
  2. Prince Yuge (? - 699), also a son of Emperor Temmu
  3. Prince Takechi (654? - 696), also a son of Emperor Temmu, general of Jinshin War, Daijō Daijin
  4. Isonokami Ason Maro (640 - 717), a descendant of Mononobe clan and in charge of Fujiwara-kyo after the capital was moved to Heijo-kyo
  5. Kudara no Konikishi Zenko (617-700), a son of the last king of Baekje, one of the Three Kingdoms of Korea.
The Cultural Affairs Agency of Japan is considering taking apart the stone chamber and reassembling it elsewhere to prevent further deterioration to its wall paintings. A painting called Asuka Bijin, or "beautiful women", is one of the murals in the tomb facing deterioration. The unusual preservation method is being considered because the tomb's current situation makes it impossible to prevent further damage and stop the spread of mold.
Unlike the Kitora Tomb, also in Asuka, removing pieces of the Takamatsuzuka wall plaster and reinforcing them for conservation appears difficult because the plaster has numerous tiny cracks.

Shinju-kyo

Japanese Shinjūkyō (神獣鏡, "deity and beast mirror") is an ancient type of round bronze mirror decorated with images of gods and animals from Chinese mythology. The obverse side has a polished mirror and the reverse has relief representations of legendary Chinese shen (神 "spirit; god"), Xian (仙 "transcendent; immortal"), and legendary creatures.
The shinjūkyō style of bronze mirror originated in China and was frequently produced during the Han Dynasty, Three Kingdoms, and Six Dynasties (1st-6th centuries CE). With the spread of Chinese bronze casting technology, shinjūkyō were also produced in Japan and the Lelang Commandery and Daifang Commandery in Korea. The ca. 297 CE Wei zhi (魏志 "Records of Wei"), which is part of the Sanguo zhi (三國志 "Records of the Three Kingdoms"), has the first historical reference to bronze mirrors in Japan. It chronicles tributary relations between Queen Himiko of Wa (Japan) and the Wei court, and records that in 239 CE, Emperor Cao Rui sent presents to Himiko, including "one hundred bronze mirrors" (tr. Tsunoda 1951:15).
Archeological excavations of Japanese tombs from the Kofun period (3rd-7th centuries CE) have revealed numerous shinjūkyō, and Japanese archeologists divide them into subtypes including:
  • sankakuen-shinjūkyō (三角縁神獣鏡, "triangular-rimmed deity and beast mirror")
  • gamontai-shinjūkyō (画文帯神獣鏡, "wide image-band deity and beast mirror")
  • hirabuchi-shinjūkyō (平縁神獣鏡, "flat-rimmed deity and beast mirror")
Kurotsuka kofun tomb excavated in Nara Prefecture contained 33 sankakuen-shinjūkyō bronze mirrors. Some scholars (Edwards 1998, 1999, Nishikawa 1999) believe they are the original mirrors that Emperor Cao Rui presented to Queen Himiko, but others disagree.


from: http://en.wikipedia.org/wiki/Shinju-kyo

Kōgoishi

Kōgoishi (神篭石 or 神籠石) are earthenwork structures, on a stone foundation, constructed in Japan during the Asuka period, particularly in areas around Fukuoka, on the island of Kyūshū. The name "kōgoishi" means "stones of divine protection", a name given them by the Meiji period archaeologist Tsuboi Shōgorō, who conjectured that they served as spiritual or practical protection for sacred sites.
Kōgoishi date to the 6th or 7th century CE, and are found predominantly in northern Kyūshū and on the shores of the Inland Sea. The longest one to be found, at 2.3 km in length, lies near the summit of Mt. Kōra, near Fukuoka. The stones there are roughly one meter long, 50 cm high and 70 cm thick.
Scholars after Tsuboi determined that the structures are most likely the remains of practical, military fortifications, and were unlikely to have significant spiritual connections. The style and form of the ruins matches many in Korea; the period when these were built was one of flourishing contact with Korea, and it is theorized that Korean stoneworkers, artisans, and architects may have played a role in the construction of these fortresses. Some scholars believe that some kōgoishi were built in anticipation of an attack from Korea, but little evidence has been found to confirm this.


from: http://en.wikipedia.org/wiki/K%C5%8Dgoishi

Haniwa

The Haniwa (埴輪) are terra cotta clay figures which were made for ritual use and buried with the dead as funerary objects during the Kofun period (3rd to 6th century AD) of the history of Japan.
During the Kofun period, a highly aristocratic society with militaristic rulers developed. The cavalry wore iron armor, carried swords and other weapons, and used advanced military methods like those of Northeast Asia. Many of them are represented in Haniwa figurines for funerary purposes.
The most important of the haniwa were found in southern Honshū—especially the Kinai region around Nara—and northern Kyūshū. Haniwa grave offerings were made in numerous forms, such as horses, chickens, birds, fans, fish, houses, weapons, shields, sunshades, pillows, and male and female humans. Besides decorative and spiritual reasons of protecting the deceased in his afterlife, these figures also served as a sort of retaining wall for the burial mound.
Because these haniwa display the contemporary clothing, hairstyle, farming tools, and architecture, these sculptures are important as a historical archive of the Kofun Period.

The origin of Haniwa

The origin of haniwa started during the latter part of the Yayoi Era around the Kingdom of Kibi. During this time special earthenware figurines and bowls started to appear on top of the tombs of leaders. The early sculptures exceeded 1 meter (3 feet) in length. They consisted of a cylindrical portion which represented the torso, and a skirt-shaped portion at the base, which represented the legs. Many times a special insignia or pattern would be displayed on the torso. Sometimes an obi would be placed around the torso portion of the sculpture. These sculptures are thought to have been used as part of a funeral ritual. Other than the Kibi area, the only other place these sculptures were found was in the Izumo province.
During the latter part of the 3rd century AD, these sculptures started to appear on top of the imperial grave mounds in the Kinai region. During this time more elaborate haniwa would appear along with earthenware bowls. It is believed that the movement of these sculptures and haniwa from the Kibi region to the Kinai region is indicative of an increase in the importance.

Later development of the Haniwa

During the earlier part of the Kofun period (latter 3rd century A.D.) the only earthenware haniwa were of the cylindrical variety; however, towards early 4th century AD, shield and other tool-shaped haniwa started to appear. Additionally, during the middle Kofun period (mid-5th century C.E.) shrine maiden, horse, dog and other animal-shaped haniwa were introduced. As the practice of having ceremonial burial mounds declined in the mid 6th century C.E., haniwa became rarer in the Kinai region; however, the haniwa were still made in abundance in the Kantō region.

Significance of the Haniwa

Originally, the cylindrical type haniwa were set on top of the funeral mounds, so it is believed that they had a
purpose in funeral rituals; however, as the haniwa became more developed, they were set towards the outside of the grave area, and it is thought that they were used as boundary markers to mark the borders of the gravesite.
There is a theory that the soul of the deceased would reside in the haniwa, as the earlier haniwa were placed on top of the funeral mounds. There are haniwa that are equipped with weapons and armor, and these are also thought to be containers for souls. The armor and weapons would serve the purpose of driving away evil spirits and protecting the buried ruler from calamity. Because the horse and animal shaped haniwa were normally neatly arranged into a line, it is believed that they were part of a sending-off ceremony.

The Haniwa in modern society

Although the religious implications of the haniwa have largely declined in modern society, the sculptures are still prized by many for their aesthetic and historical significance. The works of Shojiro Ishibashi, for example, were heavily influenced by the haniwa. They have been accepted as "Pure Art", according to Time magazine. Beyond simple appreciation as artistic sculptures, modern popular culture has, in some cases, even portrayed the haniwa as containing an actual sentient entity and not just as a simple empty sculpture. The most common portrayal depicts the haniwa with a rounded, pot-like shape, bearing two deep eyes, a wide mouth, and two featureless "arms" on opposite sides of the "pot".
The portrayal of living haniwa has—since the late 1990s—become widespread, being featured in trading cards, video games, and television. However, as with many modern portrayals of ancient spiritual beliefs (such as the banshee), the cultural aspect of haniwa is almost always overlooked. Instead, in many of the depictions, the haniwa is primarily presented as a ghostlike, malevolent creature, without attempting to retain the historical aspect of the haniwa's religious nature.


from: http://en.wikipedia.org/wiki/Haniwa

Natsumi Temple Complex

The former Natsumi Temple (夏見廃寺 Natsumi-haiji) was a Buddhist temple complex during the Nara period in the city of Nabari, Mie Prefecture, Japan. It was built under a vow of Princess Oku in remembrance of her dead father, Emperor Temmu. The structures were burnt out in the end of the 10th century, but the foundations were found through the excavation by Kyoto University in May 1946. Today, the site of this temple is a part of Nabari City Central Park.
The foundations of the main hall, a pagoda, a lecture hall, and surrounding buildings are preserved.
Investigation makes it clear that Natsumi Temple's main hall had the same design as that of Asuka's Yamada-dera, which was one of this period's major temples. The fact means that the priests of this temple were keeping good connections with the central government.
The Exhibition Hall near the site displays and explains the articles dug up at the site and the molded Buddhas, with which it is said the main hall was decorated.




from: http://en.wikipedia.org/wiki/Natsumi_Temple_complex

Mitsumine Castle

Mitsumine Castle (三峰城 Mitsumine-jō) was a castle located in present-day Sabae, Fukui Prefecture, Japan. It was constructed during the Nanbokucho period of the 14th century (part of the early Muromachi period). In 1337, Following the war between the Southern and Northern courts, Mitsumine Castle was built as a strong strategic point atop Mt. Mitsumine (from which it received its name). It was governed over by Yoshisuke Wakiya, under the orders of Yoshisada Nitta, the high ranking head of the Southern Court; however, in 1340 Shigeyuki Miyama of the Northern Court laid siege to the castle. This siege ended with the death of Miyama and destruction of the castle.


from: http://en.wikipedia.org/wiki/Mitsumine_Castle

Kusado Sengen

Kusado Sengen (草戸千軒 kusado sengen) is the name of a medieval town in Japan. It is located near the Ashida River in present day Fukuyama City, Hiroshima Prefecture. Investigators believe that Kusado Sengen was a minor commercial port town on the Seto Inland Sea during the Kamakura and Muromachi periods.

Discovery

Kusado Sengen was discovered in 1931 when a large quantity of pottery, porcelain and gravestones were discovered while attempting to re-route the Ashida River. Many historians believed that it was the site of a medieval town named Kusado Sengen. Excavation was not carried out, and the site was buried by a sandbank in the re-routed river.
 

Excavation

Excavation of the site was started in 1961 by the Fukuyama Municipal Board of Education. Several items dating back to the Kamakura and Muromachi Periods were found, and it became obvious that the site was indeed Kusado Sengen. The Ministry of Construction planned river improvements and the construction of a dam. These plans caused the possibility that the sandbank on which the site was located might be destroyed or completely submerged. Serious and long-term investigations therefore became urgently necessary. Accordingly, the Hiroshima Prefectural Institute for the Kusado Sengen-cho Site Investigations was founded in 1973 as a research unit within the Hiroshima Prefectural Board of Education.
Many of the finds from the site that have been excavated are waterlogged and reasonably well preserved. Finds include wells, pits for garbage dumping, ditches, ponds, graves, and a wide range of objects such as pottery, wooden objects, stone objects, metal objects, bone tools, fabrics, and organic remains.
Pottery was very common amongst the finds at the site, the most common being earthenware. A great deal of imported pottery from Vietnam, Korea and China was found with it.
Many kinds of wooden objects were discovered. The majority of them were for daily activities such as eating and storage.
Lacquer ware bowls and dishes are regarded as common tableware in the town. These are believed to have been produced in the town, since a lot of lacquering tools were excavated from the site. On many of lacquer vessels there are designs of living things such as birds and plants.
Other finds include coins and carpenters' tools.


from: http://en.wikipedia.org/wiki/Kusado_Sengen

Obama Castle (Fukui)

Obama Castle (小浜城 Obama-jō) is a castle located in Obama, Fukui Prefecture, Japan. The castle is also known as Unpin Castle (雲浜城 Unpin-jō). In 1601 (Keichō 6), after receiving Wakasa Province due to successes in the Battle of Sekigahara, Kyōgoku Takatsugu (京極高次) built Obama Castle by using local fisherman as workers. In 1634 (Kan'ei 11), Sakai Tadakatsu (酒井忠勝) took control of the castle after the Kyōgoku family moved to Izumo near Matsue. He finally completed the castle tower with 113,000 stones in 1636 (Kan'ei 13), with the tower reaching a height of 29m.
Obama Castle was held by the Sakai family up to the Meiji Restoration in 1868. It was destroyed in a fire in 1871 (Meiji 4) after acting as the prefectural office since the Meiji Restoration, and only the stone walls remain today. The ruins are often referred to as Obama Castle Ruins (小浜城跡 Obama-jō Ato) in tourist brochures.

from: http://en.wikipedia.org/wiki/Obama_Castle_(Fukui)

Jumat, 18 Juni 2010

Tulor

Tulor is an archaeological site located in the Norte Grande natural region of the Antofagasta Region, Chile near San Pedro de Atacama. The site is a former village complex with an area of 5,200 m2 (55,972 sq ft) and 22 outlying edifices. The settlement's remains are distributed in an east-west fashion along 2 km (1 mi). Radiocarbon and thermoluminescence dating date the origin of the settlement sometime between 380 BCE and 200 CE, but most structures are from the period 800 CE - 1200 CE. Architectural characteristics of Tulor are circular walls are made of mud and vaults.



from: http://en.wikipedia.org/wiki/Tulor

Lasana

Lasana is a small village located 40 km (25 mi) northeast of the city of Calama in the Calama province of Chile's northern Antofagasta Region. It sits along the banks of the Loa River.
Pukará de Lasana, (from Quechua Pukara: fortress), a pre-Columbian fortress built in the 12th century, is the main architectural attraction of the village. It is located 8 km (5 mi) north of San Francisco de Chiu Chiu and was declared a national monument in 1982.
Petroglyphs can also be found in the area.



from: http://en.wikipedia.org/wiki/Lasana

Atacama Giant

The Atacama Giant (Spanish: Gigante de Atacama) is a large anthropomorphic geoglyph in the Atacama Desert, Chile. Located at "Cerro Unitas", this is the largest prehistoric anthropomorphic figure in the world with a height of 86 metres (282 ft) and represents a deity for the local inhabitants from 1000 to 1400 CE.
The figure was an early astronomical calendar for knowing where the moon would set; by knowing this the day, crop cycle, and season could be determined. The points on the top and side of the head would say what season it would be depending on their alignment with the moon, which was very important in determining when the rainy season would come in the barren Atacama.


from: http://en.wikipedia.org/wiki/Atacama_Giant

Areopagus

The Areopagus or Areios Pagos (Greek: Άρειος Πάγος) is the 'Rock of Ares', north-west of the Acropolis, which in classical times functioned as the high Court of Appeal for criminal and civil cases in Athens. Ares was supposed to have been tried here by the gods for the murder of Poseidon's son Alirrothios (a typical example of an aetiological myth). In The Eumenides of Aeschylus (458 BC), the Areopagus is the site of the trial of Orestes for killing his mother (Clytemnestra) and her lover (Aegisthus).
Phryne, the hetaera from 4th century BC Greece and famed for her beauty, appeared before the Areopagus accused of profaning the Eleusinian mysteries. Legend has it that she let her cloak drop, so impressing the judges with her almost divine form that she was summarily acquitted.
The origin of its name is not clear. In Greek pagos means big piece of rock. Areios could have come from Ares or from the Erinyes, as on its foot was erected a temple dedicated to the Erinyes where murderers used to find shelter so as not to face the consequences of their actions. Later, the Romans referred to the rocky hill as "Mars Hill," after Mars, the Roman God of War. Near the Areopagus was also constructed the basilica of Dionysius Areopagites.
In pre-classical times (before the 5th century BC), the Areopagus was the council of elders of the city, similar to the Roman Senate. Like the Senate, its membership was restricted to those who had held high public office, in this case that of Archon. In 462 BC, Ephialtes put through reforms which deprived the Areopagus of almost all its functions except that of a murder tribunal in favour of Heliaia.
In an unusual development, the Areopagus acquired a new function in the 4th century BC, investigating corruption, although conviction powers remained with the Ecclesia.
The Areopagus, like most city-state institutions, continued to function in Roman times, and it was from this location, drawing from the potential significance of the Athenian altar to the Unknown God, that the Apostle Paul is said to have delivered the famous speech, "Now what you worship as something unknown I am going to proclaim to you. The God who made the world and everything in it is the Lord of heaven and earth and does not live in temples built by hands." ( Acts 17:24)
The term "Areopagus" also refers to the judicial body of aristocratic origin (the power of which was enhanced by Solon) that subsequently formed the higher court of modern Greece.


from: http://en.wikipedia.org/wiki/Areopagus

Discophoros

The Discophoros, also spelled Discophorus, (Greek - "Discus-Bearer") was a bronze sculpture by the classical Greek sculptor Polyclitus, creator of the Doryphoros and Diadumenos, and its many Roman marble copies. (It is not, however, to be confused with Discobolus of Myron, which shows a discus being thrown not carried.)
Like the Doryphoros and Diadumenos, it was created as an example of Polyclitus's "canon" of the ideal human form in sculpture. It features a young, muscular, solidly-built athlete in a moment of thought between disrobing ready to throw the discus and actually throwing it. The marble copies that feature the addition of a marble tree stump - marble is weaker but heavier than bronze, so the stump is needed for support. These copies are also often missing their arms, which are equally often restored.




from: http://en.wikipedia.org/wiki/Discophoros

Ingá Stone

The Ingá Stone (Pedra do Ingá in Portuguese) is located in near the small city of Ingá in Paraíba State in the northeast of Brazil. The Ingá Stone is also called Itacoatiara do Ingá. The word Itacoatiara means stone in the Tupi language of the natives that lived in that area.
It is composed of some basalt stones covered with symbols and glyphs undeciphered until now. Scholars think it was created by natives that lived in the area until the 18th century, although as with most ancient monuments, some people claim extraterrestrial origin.[citation needed]
Most glyphs represent animals, fruits, humans, constellations (including the Milk Way), and other unrecognizable images.


from: http://en.wikipedia.org/wiki/Ing%C3%A1_Stone

Kofun

Kofun are megalithic tombs or tumuli in Japan, constructed between the early 3rd century and early 7th century. They gave their name to the Kofun period (middle 3rd century - early-middle 6th century). Most of the Kofun have a keyhole-shaped mound (zenpo-koenfun), unique to ancient Japan.

Layout

The kofun tumuli have taken various shapes through history. The most common type of kofun is known as a zempō-kōen-fun , which has a shape of a keyhole, having one square end and one circular end, when looked down upon from above. There are also circular type (empun), "two conjoined rectangles" type (zempō-kōhō-fun), and square type (hōfun) kofun. Orientation of kofun is not specified. For example, in the Saki Kofun group, all of circular parts are looking toward the north, but there is no such formation in the Yanagimoto kofun group. Haniwa, terracotta figures were arrayed above and in the surroundings to delimit and protect the sacred area.
Kofun range in size from several meters to over 400m in length. The largest kofun is Daisen kofun in Sakai City, Osaka Prefecture, which has been attributed to be the tomb of the Emperor Nintoku.
The funeral chamber was located beneath the round part and consisted of a group of megaliths. In 1972, the unlooted Takamatsuzuka Tomb was found in Asuka and some details of the discovery were revealed. Inside the tightly assembled rocks, white lime cement plasters were pasted and colored pictures drawn depicting the court or constellations. A stone coffin was placed in the chamber and accessories, swords and bronze mirrors were laid both inside and outside of the coffin.

Development history

Yayoi period

Most of the tombs of chiefs in the Yayoi period were square-shaped mounds surrounded by ditches. The
most notable example in the late Yayoi period is Tatetsuki Mound Tomb in Kurashiki, Okayama. The mound is about 45 meters wide and 5 meters high, has a shaft chamber. Broken pieces of Tokushu-kidai, cylindrical earthenwares were excavated around the mound.
Another prevailing type of Yayoi period tombs is Yosumi tosshutsugata funkyûbo, square mounds whose four corners protruding outward. These tombs were built in the San'in region, coastal area of the Sea of Japan. Unearthed articles indicate the existence of alliances between native tribes in the region.

Early Kofun period

One of the first keyhole-shaped kofun was built in the Makimuku area, the southeastern part of the Nara Basin. Hashihaka Kofun, which was built in the middle of the 3rd century, is 280 meters long and 30 meters high. Its scale is obviously different from previous Yayoi tombs. During the next three decades, about 10 kofun were built in the area, which are now called as the Makimuku Kofun Group. A wooden coffin placed on the bottom of a shaft, and the surrounding walls were built up by flat stones. Finally megalithic stones placed as a roof. Bronze mirrors, iron swords, magatama, clay vessels and other artifacts were found in good condition in undisturbed tombs. Some scholars assume the buried person of Hashihaka kofun was the shadowy ancient Queen Himiko of Yamataikoku, mentioned in the Chinese history texts. According to the books, Japan was called Wa, which was the confederation formed by numerous small tribes or countries. The construction of gigantic kofun is the result of the relatively centralized governance structure in the Nara Basin, possibly the origin of the Yamato polity and the Imperial linage of Japan.

Mid-Kofun period

The trend of keyhole kofun first spread from Yamato Province to Kawachi, where gigantic kofun such as Daisen Kofun of the Emperor Nintoku were built, and then throughout the country (except for the Tōhoku region) in the 5th century. The spreading of keyhole kofun is generally assumed to be evidence of the Yamato court's expansion in this age. However, some argue that it simply shows the spreading of culture based on progress in distribution, and has little to do with political breakthrough. In recent years, as South Korea became more affluent after years of war and hardship, they started to allocate more resources into archeology and keyhole tombs were found in areas of ancient Gaya confederacy. These keyhole tombs discovered so far on the Korean peninsula were built from the 5th to the 6th century. Whether the Gaya keyhole tomb was due to a local chieftain influenced by Japanese culture or for a Japanese immigrant is debated "Still now, many Korean and Japanese scholars have concentrated on the issue of who are the owners of the keyhole-shaped tombs in Korean peninsula."
Keyhole-shaped kofun disappeared in late 6th century, probably because of the drastic reformation in the Yamato court, where Nihon Shoki records the introduction of Buddhism during this era.

Recent research

The Imperial Household Agency designates 740 kofun as the tomb of ancient imperial family members and their relatives, although the accuracy of the designation has been disputed. These kofun are not open to the public, including archaeologists. Academic societies repeatedly petitioned for archaeological surveys of kofun for years, and in March 2008 the Agency permitted limited investigation of Gosashi Kofun which is designated as the tomb of Empress Jingū.

Aerial photos of the notable kofun groups

 Restriction of access to Gosashi

In 1976 Japan stopped all foreign archeologists from studying the Gosashi tomb which is supposed to be the resting place of Empress Jingū. Prior to 1976 foreigners did have access. In 2008, Japan allowed limited access to foreign archeologists, but the international community still has many unanswered questions. National Geographic wrote that Japan "has kept access to the tombs restricted, prompting rumors that officials fear excavation would reveal bloodline links between the "pure" imperial family and Korea." Experts still hope Japan will be more forthright in the future and see this limited access as the first step in the right direction. These controversies make interpretation of the Nihongi, Book of Song/Sui and Samguk Sagi inconclusive and until further analysis of restricted tombs and artifacts are evaluated, it is difficult to draw conclusions.

 

from: http://en.wikipedia.org/wiki/Kofun