The Japanese Never Left: Continuous Habitation of the Japanese Archipelago

The question "When did the Japanese return to Japan?" rests on a false premise: the Japanese people have continuously inhabited the Japanese archipelago for at least 35,000–40,000 years. There was no departure, exile, or mass migration requiring a "return."

Deep Continuity

• Paleolithic (35,000+ BCE): First modern humans arrive via land bridges (lower sea levels). Stone tools, no pottery.
• Jōmon Period (14,000–300 BCE): Hunter-gatherers with world's earliest pottery (16,500 BCE). Sedentary/semi-sedentary villages, rich material culture. Ancestral to Ainu and modern Japanese.
• Yayoi Period (300 BCE–300 CE): Rice agriculture, metallurgy (bronze/iron), new migrants from continent (Korea/China). Population explosion. Genetic admixture.
• Kofun Period (250–538 CE): Keyhole tombs, early state formation, Yamato polity emerges.
• Asuka/Nara/Heian (538–1185): Centralized imperial state, Buddhism, Chinese-style bureaucracy, kana writing, Tale of Genji.
• Medieval/Feudal (1185–1868): Shogunates (Kamakura, Muromachi, Tokugawa), samurai, castle towns, sakoku (isolation 1639–1853).
• Modern (1868–present): Meiji Restoration, industrialization, empire, WWII defeat, occupation, economic miracle, current democracy.

Why the Misconception?

• WWII Repatriation: ~6.6 million Japanese civilians/soldiers returned from overseas (Manchuria, Korea, Taiwan, Sakhalin, Pacific islands, SE Asia) 1945–1947. This was a return from empire, not from Japan.
• Sakoku (Closed Country): 1639–1853 limited foreign contact. Not Japanese leaving Japan.
• Emigration: 1885–1940: ~1M Japanese migrated (Hawaii, Americas, Brazil, Peru). Diaspora, not depopulation.
• Mythological "Descent from Heaven": Ninigi-no-Mikoto (grandson of Amaterasu) descended to Kyushu. Origin myth, not historical return.

Genetic & Cultural Continuity

Modern Japanese (~125M) derive from Jōmon + Yayoi ancestry with minor later inputs. Language (Japonic), Shinto, cultural practices show unbroken evolution. No population replacement event.

The Japanese are of Japan—emerged there, evolved there, never left. The question reflects a colonial/expulsion narrative that doesn't apply.