From the seventeenth to the twentieth century, rivers played a key role in the colonization of Hokkaido, a northern island in the Japanese archipelago. The Kushiro River, in eastern Hokkaido, was transformed into infrastructure, a process which shaped the institutions, strategies, and practices of territorial control during the transition from the Tokugawa shogunate (1603–1868) to Imperial Japan (1868–1947). Trade between local Ainu communities and the shogunate's vassals contributed to a river-based territoriality. Later in the 1800s, as the island became territory of the modern state, the river was further converted into infrastructure through settler colonialism, industrial development, land reclamation, and the dispossession of indigenous communities. This transformation empowered the state to probe territories, exert control over labor, and access natural resources. Drawing on research on the political ecology of rivers, this paper focuses on two hydrosocial functions that emerged during the process of reworking river basins into legible and governable spaces: the transportation conduit and the water delivery system. The river's transition from a living system to infrastructure coincided with and furthered the establishment of colonial settlements and the expansion of the Japanese state's imperial reach.

The return of remains of Korean forced laborers who died in Japan between 1940 and 1945 has been a major controversy for over half a century for Koreans. These deaths reveal the tragic consequences of Japan’s World War II forced labor system. Japan forcefully mobilized nearly 800,000 Koreans who were taken to at least 1,589 worksites in Japan and 381 worksites in Hokkaido. Over 10 percent of all Koreans forcefully mobilized throughout the empire are estimated to have died or disappeared, but the precise number of Korean forced laborers’ deaths inside Japan remains unknown. Until 1989, remains recovered from graves throughout Japan by local people were immediately cremated by Japanese Buddhist priests, making cause of death and precise identities forensically impossible. This account relates the first and only comprehensive effort to exhume Korean forced labor graves without immediate cremation, coordinated by Korean and Japanese activists and academics based in Hokkaido. This effort helped revive a neglected aspect of Korean forced labor history while focusing on the concerns of bereaved Koreans seeking the remains of their lost family members. Nevertheless, the project had serious limitations due to working in a difficult political environment and neglect of forensic science protocols in mass grave excavations and identification. This complex situation prevented identification of victims’ names and cause of death that could have held the Japanese government and companies involved accountable.

This article examines how Japanese colonial migration to Hokkaido in the first two decades of the Meiji era paved the way for Japanese trans-Pacific migration to the United States in the 1880s. It elaborates how Japanese leaders carefully emulated the Anglo-American settler colonialism in Japan's own expansion in Hokkaido by focusing on the emergence of the overpopulation discourse and its political impact in early Meiji. This colonial imitation also inspired the Japanese expansionists to consider the American West an ideal destination for Japanese emigration in the late nineteenth century. This study thus challenges the nation-centered and territory-bound history of the Japanese empire by showing that Japan's colonial expansion in Northeast Asia and Japanese trans-Pacific migration to North America were intertwined since the very beginning of the Meiji era.

Okhotskite, an Mn3+-dominant pumpellyite-group mineral, is monoclinic, A2/m, a = 8.887, b = 6.000, c = 19.55 Å, β = 97.08°, Z = 1. The formula is

(Ca7.63Na0.17K0.01)Σ7.81(Mn2.752+Mg1.10)Σ3.85(Mn4.503+Al1.87Fe1.613+Ti0.02)Σ8.00Si12.13O39.71(OH)16.29,

which simplifies to Ca8(Mn2+,Mg)4(Mn3+,Al,Fe3+)8Si12O5∂-n(OH)n. Strong lines in the X-ray powder diffraction pattern are: 4.76(60)(004, 111), 3.87(70)(202), 2.96(100)(115, 300), 2.88(25)(022), 2.72(70)(302), 2.67(45)(3̄04, 3̄11), 2.55(45)(024, 3̄13) and 2.38(45)(304).

Its colour is deep orange with a pale orange streak and vitreous lustre. Transparent. Non-fluorescent. H6 (Mohs). Density (calc.) = 3.40 g/cm3. Optically biaxial negative, 2V(meas) = 46(5)°, 2V(calc) = 46°, dispersion indiscernible. Refractive indices: α = 1.782(5), β = 1.820(5), γ = 1.827(5). Orientation: Y = b, c∧Z = 9–14° in acute angle of β. Pleochroism is distinct: X yellow, Y and Z deep orange. Absorption: X < Y < Z.

This mineral occurs as fine prisms up to 0.2 mm long and forms aggregates in network veinlets cutting hematite ore from the Kokuriki mine in the Tokoro district, eastern Hokkaido, Japan. Associated minerals are: hematite, piemontite, quartz, neotocite, bementite, apatite, Mn-oxides, inesite and rhodochrosite. The mineral is named okhotskite for the Sea of Okhotsk, along which the mine is located.

At the Akkeshi estuary, rapid emergence interrupted Holocene submergence at least four times in the past 3000 years. Each emergence event produced an upward change from estuarine mud to freshwater peat. While the estuarine mud abounds in brackish and marine diatoms, freshwater taxa dominate the peat. Emergence events occurred from 1700 to 2300, 1000 to 1300, and 500 to 700 cal yr B.P. An additional emergence event predated by several decades a volcanic ash that erupted in A.D. 1694. At least three of the events produced contacts abrupt enough to represent uplift during earthquakes. Such uplift may reconcile seemingly conflicting records of vertical crustal movement in eastern Hokkaido. This tectonically active area, which is being subducted by the Pacific plate at 8 cm/yr, contains marine terraces that imply 0.1–0.5 mm/yr of net uplift in the late Quaternary. However, these terraces adjoin tide gages that recorded 8–9 mm/yr of steady submergence in the 20th century. The terrace uplift need not conflict with the gaged submergence if the region is subject to occasional coseismic uplift, as during the emergence events implied by Holocene geology near Akkeshi.

In Itō Sei's (1905–69) “Yūki no machi” (Streets of ghosts, 1937), a narrator returns to his native town of Otaru, Hokkaido, where he experiences a hellish and hallucinatory encounter with people from his past. He is forced to confront shameful aspects of his youthful life that he had tried to repress. In this paper, I propose that a close examination of the story sheds useful light on the real fears, tensions and expectations surrounding colonialism that had become an integral part of Japanese culture and society during the late 1930s. Structures of colonialism, which speak of uneven power relationships between a dominant centre and a distant weaker locality, are spelt out, for example, through the railway network and racist ideology that appear in the story. I also explore the story's depiction of a colonial relationship between mainland Japanese culture centred round Tokyo and the peripheral outpost of Hokkaido. More generally, I suggest that the story illuminates a global power configuration between Japan and its colonies that was entering an increasingly aggressive and bellicose phase during the late 1930s.

Stratigraphic fluctuations of carbon isotope values of terrestrial organic matter within the Upper Cretaceous (Cenomanian–Santonian) sequence in the Obira area of Hokkaido, Japan, record distinctive δ13C fluctuations for the Cenomanian–Turonian boundary, the Middle Turonian, the upper Turonian–lower Coniacian, and the Santonian. A biostratigraphic framework of the age-diagnostic taxa (ammonoids, bivalves and planktic foraminifers) indicates that these δ13C fluctuation events are comparable with those recorded in δ13C data of terrestrial organic matter in Japan and marine carbonates in Europe. These correlations reinforce the utility of these δ13C events in terms of global chemostratigraphy. In particular, the δ13C patterns within the overall positive interval of the Cenomanian–Turonian boundary event are highly conformable between marine and terrestrial records. The consistent nature of these different records of δ13C fluctuation patterns demonstrates that the terrestrial organic δ13C data mirror the global-scale δ13C patterns in the carbon reservoir of ocean–atmosphere–terrestrial biosphere during the Cenomanian–Turonian boundary event. In addition, global correlation of short-term marine and terrestrial organic δ13C fluctuations of the Upper Cretaceous sequence indicate that the magnitude of several terrestrial organic δ13C events appears more amplified than that of coeval marine carbonate δ13C events. This correlation is interpreted to mean that the effects of local CO2 emission into the atmosphere by release of terrestrial methane hydrate or biomass burning of terrestrial vegetation in the hinterland of the NE Asian region have been superimposed on the global δ13C trend and resulted in the terrestrial organic δ13C records of the Yezo Group.

Habitat-use by Steller's sea eagle Haliaeetus pelagicus, categorized as Vulnerable on the 2002 IUCN Red List, was studied using satellite-tracking. This migratory species breeds in eastern Russia and mostly overwinters in Hokkaido, Japan, and the southern Kuzíl islands. Locations of eagles were classified as being river, sea, lake, or other habitat. In autumn, eagles mainly used river habitats, probably because of the availability of abundant post-spawn dead salmon. In winter about one third of eagles continued to be located on rivers, with others on sea coasts and lake sides. During the spring migration and breeding season habitat use by adult eagles probably reflected the variety of habitats in which breeding occurs. At that time, sub-adult eagles were located mainly on the sea coast, probably in places where food supply was sufficient and there were few territorial eagles. In Hokkaido 35% of overwintering eagles used mountain areas for at least some time. It is known that eagles using mountain areas in Japan in winter scavenge upon the carcasses of sika deer Cervus nippon killed by hunters, and are thus exposed to possible lead poisoning. The satellite tracking highlights the importance of several habitats within the range of this species, changes in which could affect its conservation status.