Component 2, Part 1
Centripetal Forces in Japan: The Physical Setting

The Japanese archipelago consists of four major islands and numerous smaller islands. The archipelago is separated from the Asian mainland by the Sea of Okhorsk, the Sea of Japan, and the East China Sea (Figure 1). Japan is the "Land of the Rising Sun" as depicted on the Japanese flag (Figure 2).

Because this is an island nation there have historically been strong physical barriers to migration. Not only are there three seas to the west, but there is the expanse of the Pacific Ocean to the east. The strong, warm Kuroshio Ocean current travels northward along the east coast of Japan. The cold Oyashio current flows south along the coast of Asia. The Oyashio meets the Kuroshio off the east coast and fogs develop along the boundary between the currents. The cold, foggy condition known as yamase can occur from June to mid-August in northern Japan adding localized climatic barriers.

Japan's Neolithic people, the Jomon Culture (ca. 10,000 BCE - ca. 300 BCE) used the marine and coastal resources (Karan, 2005). Japan extends across 24 degrees of latitude, which would be similar to going from Boston to Mexico City in North America. This expanse, plus the climatic variations and the insular and ocean current factors limiting access, accounted for some of the isolation and separate development. It was during the Yayoi Period (ca. 300 BCE - ca. 300 CE) that Mongoloid immigrants crossed the Strait of Tsushima separating Japan from the Korean Peninsula in significant numbers bringing the knowledge of rice paddy cultivation, weaving, and smelting of iron. Although greatly influenced by contact with Korean and Chinese cultures, the Japanese began before 1000 CE to form what is now considered largely an ethnically homogeneous state. The Portuguese and other Europeans did not arrive until the mid-sixteenth century after centuries of cultural development had taken place with the physical barriers still in place. The barriers limited immigration and contact and aided the Japanese in becoming, for the most part, an ethnically homogeneous society. Even though Japan imported a writing system from China via Korea, the Japanese, despite regional dialects, shared a common spoken language. This acted as a centripetal force.