A series of paleogeographic maps of the Japanese Islands, from their birth at ca 750–700 Ma to the present, is newly compiled from the viewpoint of plate tectonics. This series consists of 20 maps that cover all of the major events in the geotectonic evolution of Japan. These include the birth of Japan at the rifted continental margin of the Yangtze craton (ca 750‐700 Ma), the tectonic inversion of the continental margin from passive to active (ca 500 Ma), the Paleozoic accretionary growth incorporating fragments from seamounts and oceanic plateaux (ca 480‐250 Ma), the collision between Sino‐Korea and Yangtze (250–210 Ma), the Mesozoic to Cenozoic accretionary growth (210 Ma‐present) including the formation of the Cretaceous paired metamorphic belts (90 Ma), and the Miocene back‐arc opening of the Japan Sea that separated Japan as an island arc (25‐15 Ma).

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Ultrahigh‐pressure metamorphic (UHPM) rocks of the Kokchetav Massif of Kazakhstan contain metamorphic microdiamond and coesite inclusions inside rigid capsules such as garnet and zircon. Precambrian protoliths of the UHPM rocks were metamorphosed at around 530 Ma, at pressures of about 7 GPa, which suggests that crustal protoliths were subducted to depths of over 200 km. Primary UHPM minerals are poorly preserved due to partial obliteration by subsequent Barrovian overprint during exhumation and later collision events in Caledonian times. We report the results of detailed mapping of the Kokchetav Massif and use structural data to propose intrusion and exhumation mechanisms for the UHPM rocks. Detailed mapping revealed that many subvertical structures in the ultrahigh‐pressure–high‐pressure (UHP–HP) units were formed due to later folding. The primary structure appears to be subhorizontal and the total thickness of the UHP rocks is estimated at around 2 km. The first order structure is sandwich‐like; that is, the UHP–HP units are separated from underlying low‐P metamorphic rocks of the Daulet Series and from feebly metamorphosed to unmetamorphosed sedimentary strata on the top by subhorizontal faults. Kinematic indicators show top‐to‐the‐south sense of shear along the top, and top‐to‐the‐north displacement along the bottom boundaries. These shear senses, together with the observed metamorphic gradients, suggest that the thin UHPM sheet was extruded toward the north. We consider wedge extrusion to have been the most effective mechanism for the exhumation of the UHPM rocks.