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The Late Paleolithic Era was characterized by frequent volcanic eruptions. It was also a very cold period. Late Paleolithic humans lived in a severe environment, however, by the tune the Jomon Period began, the climate had grown significantly warmer. With this warming trend, the sea level also rose. As a result, what we now know as Tokyo Bay reached as far as Itakura Town, Oura-gun in Gunma Prefecture. Seasonal winds blew in winter and, on occasion, heavy snow fell on the Japan Sea side of Honshu. Consequently, this was also the end of the drying period of the Late Paleolithic Era.
This change in the environment was accompanied by the spread of broadleaf deciduous forests. The number of species of trees and plants also increased and the number of species of animals living in the forests increased proportionately. This provided new and increased sources of food for the people who were sharing the environment. It is believed that the need for new styles of food preparation may have spurred the development of pottery.
One of the main characteristics of the Neolithic Era is the use of pottery. Rolled up clay or layers of clay rings were used to construct bowls, pots, dishes and other vessels, which were then decorates with various motifs and fired unglazed. Clay pottery of the Jomon Era is divided into different periods based on the method of construction, shape and motif. Because the use of twisted cord decoration is typical of the Neolithic Era which follows the Paleolithic Era, the culture is referred to as the "Jomon" (cord-marking) Period.
The use of pottery construction, shape and motif provides a convenient way to classify the Jomon Era into six separate periods. They are: the Incipient Period (12,000 - 10,000 years before present); the Initial Period (10,000 - 6,000 years before present); the Early Period (6,000 - 5,000 years before present); the Middle Period (5,000 - 4,000 years before present); the Late Period (4,000 - 3,000 years before present); and the final Period (3,000 - 2,000 years before present).

Jomon Era clay figurine

What do we know about the Jomon Period in Kiryu?
The Cultural Assets Division of the Kiryu City Board of Education carried out a survey of all the archeological sites in the city over a four-year period, beginning in FY 1989 and ending in FY 1992. The results of the survey appear in the publication, "Kiryu City Buried Cultural Assets Distribution Map and List of Place Names" (kiryu-shi maizo bunkazai bunpu chizu chimeihyo). According to this survey, there are some 263 sites dating back to the late Paleolithic, Jomon, Yayoi and Kofun Periods of prehistoric Japan and from the Nara and Heian Periods of Ancient and Medieval Japan.
Of these sites, Jomon pottery was excavated at 163 locations. There are few sites, however, which are exclusively Jomon. Yayoi-style pottery has been excavated from 28 sites; Nara-Heian pottery has been excavated from 69 sites. Few of the sites have been thoroughly excavated and it is believed that between ten and twenty of them represent some sort of human settlement.
The following is an overview of the Jomon Period sites.
Incipient Period: Fudoana (Umedacho); Izuta, Fumonji, Ryudaiji, Sumiyoshi, Yamanokoshi (all in Hishimachi); Shinmeiyama (Hirosawacho); Kanazuka (Tsutsumicho), and others. In addition, five other confirmed locations have been found, making a total of 16 sites.

Excavation of a Jomon site

Initial Period: Kinryudai (Umedacho); Kiryugaoka Koen, Tokodai, etc. (Hishimachi). These sites have been found in elevated locations. A further 55 sites have been discovered in even higher elevations, such as along mountain ridges.
Early Period: The majority of Jomon sites in Kiryu are from the Early Period. In addition to those which had already been discovered at the time of the survey, a further 52 sites were identified, making 108 in all. For Jomon humans, the plentiful wild game to be found in the forests and fields, the rivers teaming with fish, the nuts and grains readily available, made Kiryu an optimal location for settlement. The excavation of a Jomon settlement in Dojibara, Kawauchicho 2 chome was conducted from 1992 to 1993. A large Early Jomon hamlet was discovered there. Until that excavation, it was believed that Early Jomon sites were small settlements located around the skirt of a hill or mountain. The Dojibara Site, however, was large scale, having some 22 recognizable dwellings. Because it seems to be a fossilized site of considerable size, it is thought to have been a large community.
Middle Period: Some 27 Middle Period sites were already identified at the time of the survey, however, a further 12 were discovered, making 39 in all. The largest scale hamlet is the Asabe site in Umedacho 2 chome. The remaining Middle Period sites are all small scale.
Late Period: Late Jomon Period settlements include a river bank terrace site in Umedacho and a terraced site along the Watarase River in Aioicho. In addition, seven other new sites have been identified, making a total of 15 in all.
Final Period: Final Jomon Period sites are rare in Kiryu. Only four sites have been identified, however, the Chiamigaito Site in Kawauchicho 3 chome has attained national recognition for its outstanding pottery artifacts, some of which have been declared National Cultural Assets.

Jomon Period Occupations
The climate of the Incipient and Initial Jomon Periods was somewhat warmer than our own today. On the other hand, the climate of the Late and Final Jomon Periods was colder. On the whole, it can be said that there was no great difference between Jomon climate and the climate we experience at present. For this reason, it is believed that the flora and fauna of the Jomon Era were also similar to currently extant species.
Jomon humans lived from day to day on the natural resources they were able to catch or gather with their own hands. A great many flint arrowheads have been excavated from the Chiamigaito site. From the no. 1 dwelling alone, excavated in 1982, over 1,600 arrowheads were discovered. The use of a bow and arrow for hunting is another characteristic of the Jomon Era. Flint arrowheads have been discovered at sites dating from the Initial Jomon through the Final Jomon Periods.
Birds and wild animals were a major source of food for Jomon humans. Pheasants and other species of birds, rabbits and other small game, deer, wild boar, and other large game were probably all hunted by Jomon people.
Earthen puts are often discovered at Jomon sites. It is believed that these puts may have served as traps for catching animals. Four such pits were discovered at Mijimadai, an Early Jomon site in Kawauchicho 3, 4 chome. These trap-pits are frequently found on plateaus, along elevated locations, or on the tops of ridges. An oval trap-pit, 2 meters long, 1.4 meters wide, has been excavated at the Dai site in Umedacho 5 chome.
Hunting with a bow and arrow is thought to have been practiced in winter when the cold weather hindered the movements of animals. Trap-pits, however, were probably employed year-round. Asiatic black bear, deer, boar and other game were all important sources of food which were caught in these pits, and their pelts were used for clothing. Bones of animals eaten by humans have been excavated from the Chiamigaito site. While boar and deer bones predominate, there are also bones from bears, macaques, and pheasants. In some Jomon dwellings, bones of game which had been roasted in a fire were discovered near the hearth. Some of the bones had been split open and it is believed that the inhabitants probably ate the marrow within. Marrow is the soft, highly nutritious substance in the center of bones, where blood is produced. The expression, "To suck the marrow from the bone", refers to getting everything down to the last edible bite, and, nod doubt, Jomon humans ate everything from bone marrow to brains.
It has been suggested that Jomon humans were cautious with food resources and did not trap and eat immature game, however, the roasted bones of a suckling boar have been found around the hearth of a dwelling at Chiamigaito. It was conjectured that the inhabitants may have eaten a suckling boar which had been killed in a ritual sacrifice.
Many stone weights have been found at Chiamigaito. These weights were tools used for fishing. Most are flat, oval or egg-shaped stones, 4 - 6 centimeters long and 3 - 4 centimeters wide. A groove has been cut vertically on both sides of the stones and notches are cut along these vertical grooves on both sides. The grooves and notches are used to tie them to net strings. It is believed that these stones served as fishnet singers. Fish living in the rivers were also an important source of food for Jomon humans.

Jomon fishnet sinkers

The Chiamigaito site is located on a terrace along the Watarase River, about 150 meters distant from the river itself. Nearby is Yamada Creek which flows into the Watarase, Of course, during the Jomon Era, there was no fear of copper poisoning, pollution from agriculture, or waste water from humans settlements. No doubt, the clear streams were teeming with fish. There may have been both salmon and trout, Unquestionably, Jomon humans caught sweetfish (ayu), crucian carp, and minnows. While the bones of many animals have been found, as of yet, no fish bones have been discovered, making it impossible to identify what species they were catching and eating.
During the Jomon Era, bones and horns/antlers were used to make fishing implements such as spears, harpoons and fishing hooks. It is clear, therefore, that Jomon humans caught fish with hooks and spears.
Meat and fish, however, were not the only source of food during the Jomon Period. The surrounding hills and mountains had a wealth of edible plants. In particular, walnuts, chestnuts, acorns and other types of nuts could be preserved, and it is believed Jomon humans gathered them in quantity. These nuts, however, decomposed in the soil, leaving few traces behind. Fossilized walnuts, acorns, chestnuts and horse chestnuts were found buried in a put at the Mijimadai site in one of the dwellings. At the Kinryudai site in Umedacho, fossilized nuts were excavated from what is believed to have been a storage pit.
There is no evidence of plant cultivation at the Jomon sites in Kiryu. As far as is known, Jomon inhabitants of this area subsisted on hunting, fishing and gathering.

Jomon Dwellings and Hamlets
During the Jomon Era, people lived in pit dugouts constructed by digging out a flat area of soil. The dwellings were dug about 1 meter deep and were either round, oval or rounded with corners. The floor was flat and the walls were nearly perpendicular. Over this simple dwelling, they erected a shed-like covering. The oldest pit houses in Gunma Prefecture have been found at the Yagisawa Shimizu Site in Onogami Village, Kita Gunma-gun. The dwelling is from the latter part of the Incipient Jomon Era and is 5 meters long, 4.5 meters wide, and circular in construction. The structure is enclosed by a 24 - 40 cm wall. The floor is somewhat deeper in the center. There are some 16 holes thought to have been for wooden posts which have been dug irregularly around the circumference. There was no hearth fire as has been customarily found in other put dwellings.
With the beginning of the Early Jomon Period, the number of sites steadily increases, there usually being one found on every plateau or terraced area. In Kiryu as well, many Early Jomon sites have been discovered along the Watarase River, on elevated locations along the Kiryu River, and on its tributary creeks. Many of these sites, however, have yet to be excavated archeologically.
The Mijimadai site is known to have been inhabited from the Incipient Jomon through the Middle Jomon Eras. This plateau faces south with good exposure to the sun. It has been repeatedly developed for housing, resulting in the destruction of prehistoric artifacts. In order to record what is there, the Cultural Assets Preservation Division of the Kiryu City Board of Education has excavated the area 9 times, beginning in 1977. The 1991 excavation discovered Early Jomon sites for the first time. These sites are divided into 3 blocks, with the settlements labeled numbers 1, 2 and 4. There are 3 dwellings at no. 1, 5 dwellings at no. 2, and 2 dwellings at no. 4, in an overlapping configuration. No doubt, over time, dwellings were built over previously used locations. Pottery was also discovered in the same overlapping style. In any case, there is no doubt that these were put dwellings constructed during the Early Modern Jomon Era.
The discovery of these sites also demonstrates that, even during the Early Jomon Period, humans had gathered together in groups to establish hamlet-like settlements. Some 22 Early Jomon dwellings were excavated at the Dojibara site in Kawauchicho 2 chome. This is the largest Early Jomon settlement discovered in Kiryu. It had been thought that during the Early Jomon Period only small settlements could be found in plateau areas, however, it appears that this bears rethinking. Although all 22 of the dwellings found were probably not coexistent, a sizable number of them were. Further investigation will hopefully shed light on the scale of the settlement and manner in which the inhabitants lived. The basic construction of Jomon put houses does not seem to have varied from the Early Jomon through the Final Period.
A well-preserved Early Jomon dwelling has been discovered in Ichinoseki, Miyagi Village, Seta-gun. The shape of the floor is rectangular, running about 8 meters from north to south and 5 meters from east to west. The red earthen (Kanto loam stratum) floor slopes southward; at its greatest depth, it is 1.5 meters deep, and at its shallowest, 1 meter deep. The interior floor has been pounded hard in the manner of a farmhouse. In the center, with a somewhat northerly orientation, there are several rocks grouped in a square formation which surround a hearth. In the northwest corner, a hole has been dug which is approximately 15 centimeters deep, 1 meter in length and 40 centimeters wide. This pit was used to store food.
The dwelling roof, unfortunately, no longer exists, and so we can only conjecture about its design. Holes to bury posts which served to support the roof follow the apse line of the roof. To wit, the post holes are in a north-south configuration, closely resembling a gabled roof.
Around the circumference of the floor there is a continuous series of holes, several centimeters in depth, indicating that the dwelling was surrounded by a wall, constructed of thin wooden poles between which there were no gaps. (Information taken from メGunma no Kodaishiモ [Ancient History of Gunma] by Eiji Matsushima).
Many dwelling have been discovered at the Middle Jomon hamlet located at Mijimadai. The following is a description of one of them:
The dwelling is located about 30 centimeters below the present soil surface. It is about 6.2 meters from north to south and 5.8 meters from east to west, and oval in configuration. The walls of the dwelling have been dug perpendicularly, the northern side being 57 centimeters high, the western wall being 33 centimeters high, and the eastern wall being 11 centimeters high. The height of the southern wall could not be determined during excavation.
The floor of the dwelling is exceptionally hard packed. A heath, surrounded by 11 rocks, is situated more or less in the center of the dwelling. An earthen pot, the base and lip of which are missing, is buried in the center of the hearth. A ditch has been dug around the floor of the building which ranges from 22 to 34 centimeters deep, and from 15 to 25 meters wide at the top. At the bottom of the ditch, there appears to be holes dug for posts. It is believed these posts probably served to prevent the mud walls from collapsing.
Some 14 structural posts for the dwelling have been found. On the north side, the post holes are located singularly, however, on the south side, they appear in pairs. On the southeast side of the dwelling, the post holes are grouped together, indicating that this side of the structure served as the entrance. It has been suggested that horizontal wooden poles were used to tie the vertical posts together which, from the ground up, slanted in toward the peak. Finally, a horizontal wooden pole was used to bind all the posts together and the whole structure was covered with a thatched roof.
This Jomon dwelling had rectangular projections while being oval-like in shape, and had a chimney-like opening at the top to allow smoke to escape. Around the end of the Middle Jomon Period, the soil was not dug out very deeply to form the floor of the pit houses. Instead, flat stones or riverbed rocks were laid on the floor. For this reason, these dwellings are sometimes referred to as flat stone dwellings. They are, however, few in number. In Kiryu, such dwellings have only been found at the Chiamigaito site.

Construction of a Jomon dwelling


Jomon ear ornaments from Chiamigaito

The Chiamigaito site, located in Kawauchicho 3 chome, Oaza, Sunaga-aza is perhaps the most well-known archeological site in Kiryu. The presence of this Jomon site has been known for many years. According to Iwasawa Shosaku in the Yamada-gun Shi, Chiamigaito is the most significant site in Yamada-gun. Archeological excavation, however, only began in 1947. The first excavation was undertaken by Toshio Sonoda, a teacher at Kiryu Technical High School, along with several of his students. From that time until 1972, Sonoda was in charge of the excavations at Chiamigaito. Over the years, he carried out some 21 excavations under the auspices of the Kiryu City Board of Education and before construction on the site was permitted.
Students from Sonoda's high school, along with students interested in historical research from other schools, formed the working staff for this archeological project. They worked during summer and winter vacations, or whenever a long holiday presented itself. For the most part, no public funding was provided. The research on Chiamigaito proceeded thanks to the enthusiastic archeological interest of the students and others who cooperated on the project.
The first excavation of the site, which was undertaken in August 1949 and continued through march of the following year, uncovered a collection of clay pottery characterized as "balloon knot motif" (fusen ami jomon). The report of this excavation appeared in Ryomo Antiquities, no. 2. The report stated, "a new form of clay pottery has been discovered in the Kanto area" dating from "the close of the Jomon Period and the initial stages of the Yayoi Period." As a result, Chiamigaito became representative of the transition from the Final Jomon Period to the dawn of the Yayoi Period. This landmark discovery attracted attention all over the country.
Further excavation of the site was undertaken from the end of February through the end of March 1977 and again from July of the same year for about 6 months. This extended research by the Kiryu City Board of Education came about as the result of pressure to record and preserve the site before a planned road widening scheme was undertaken. Until that time, every road or housing construction project was preceded by excavation of the site. The 31st excavation was carried out from July through September 1997.
The results of these many excavations are extraordinary by any standard. Artifacts discovered are not only great in number, but also in form and style as well. In particular, the Final Jomo Period artifacts excavated at the no. 1 and no. 4 dwellings in 1977 and 1978, have proved to be of great archeological significance. In all, some 3,297 items were excavated and declared National Important Cultural Assets.

Chiamigaito Artifacts
The artifacts found in dwelling sites range from the Middle to Final Jomon Period, however, the majority are Late Jomon. This site was inhabited over a very long period of time, and, in some cases, Final Jomon dwellings have ben found layered over Late Jomon dwellings. One of the Final Jomon dwellings excavated in 1978 is nearly square in construction with rounded corners which measure 530 centimeters by 520 centimeters. Just east of the center there is a rectangular grouping of stones which measure 70 centimeters on one side, forming a hearth. Within the dwelling, stone swords, engraved stones, clay figurines, and clay ear decorations of various forms and styles were excavated. In 1994, a stone-floored dwelling from the Middle Jomon Period was excavated. This was the first such dwelling to be discovered in Kiryu.
Jomon Period sites are frequently littered with piles of natural rocks, both large and small. Such piles of rocks have ben found at Chiamigaito as well. It is believed these sites may have served ceremonially. During the Jomon Period, Jomon society was heavily influenced by magical practices. It is believed that the engraved stones, stone swords and clay figurines were also religious articles. For a hunting and gathering society such as that of the Jomon Period, religious rituals provided a sense of security. At the site excavated in 1976, 5 groupings of rocks were found in rectangular formation, measuring 240 centimeters in height and 120 centimeters in width. It is believed these stone arrangements may have been a kind of sarcophagus. During the Jomon Period, the dead were often buried a short distance from a dwelling. The discovery of these stone sarcophagi are important for the study of Jomon burial practices.

Abundance of Forms and Styles
The people living at Chiamigaito during the Final Jomon and Early Yayoi Periods produced and employed a kind of clay pottery, characterized by its unique "balloon knot motif." This motif is also known as Chiami style and is typical of the final Jomon Period. Deep jars, shallow jars, plates, spouted vessels, pots, etc. - a great variety of sizes and shapes have been excavated.
Stone tools, as well, are also numerous. Flint arrowheads and stone axes are of particular interest. Polished stones, concave stones, pounding stones, and stone weights (sinkers) abound. The bones of animals and fish have also been excavated in great numbers. The bones of large game such as deer and wild boar, and the fangs of animals were carved into ornaments and accessories or needles, bowstring fasteners, and arrow notches (the end of the arrow which hooks onto the bowstring), all of which were used in everyday life.
In addition, religious/ceremonial objects such as rods, stone swords and stone objects known as "dokko ishi," etc. were also discovered in great abundance at Chiamigaito.
The clay ear decorations which were excavated are particularly noteworthy. It appears that Jomon people were fashionable. They wore various forms of accessories. These objects, however, were not simply decorative. In some instances, they seem to have served to ward off misfortune, and in other instances, they seem to have been used during rites of passage.
The ear decorations are also believed to have had more than just decorative significance. They were worn by piercing a hole in the earlobe which was gradually stretched around them. The ear decorations range from 1 centimeter in circumference for a small size to 10 centimeters for the large. Some are without embellishment, while others are intricately carved in relief and display open-work designs. The plainer ones may have been for everyday wear while the elaborate ones may have been for ceremonial occasions.
The large ear decoration excavated in 1978 at the no. 4 dwelling has been characterized as "open-work funnel carved motif" and is an exquisite work of art.
The accumulation of ear decorations at Chiamigaito and other nearby sites suggests that there may have been some specialization in Jomon society and that these sites many represent artist colonies.
Chiamigaito has been excavated over 30 times, resulting in the discovery of a wealth of Final Jomon Period artifacts. It is hoped that the study of the many materials this site has provided will lead to a deeper understanding of the people we know as "Jomon."

Artist's conception of a Jomon woman wearing an ear ornament

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