10세기 이전 동아시아에서 대규모로 인구가 이동하는 되는 계기는 정치적․경제적 요인 등 다양하지만 가장 중요한 요인은 연평균 기온의 변화였다. 기상학자와 기후학자, 식물학자, 지질학자 등의 학제간 연구에 의하여 동아시아에서는 대략 지금부터 5000년 동안 4차례의 온난기와 4차례의 한냉기가 있었음이 드러났다. 온난기에는 정착 농경민인 한족 세력이 서쪽, 북쪽, 남쪽을 향해 표출되어, 군사적 정복과 이주 정책을 통해 인구가 이동하였다. 반대로 한냉기 혹은 온난기에서 한냉기로 변화할 때에는 북방의 유목민이 대거 남하하여 정착 농경민을 정복하고, 남하해온 지역에서 각기 이주정권을 세우고 서로 패권을 다투었다. 이들 이주정권들은 자신들의 남하로 일어난 인구 이동 외에도, 정복한 정착민과 복속시킨 유목민을 특정 지역으로 강제로 이주시키는 정책을 취하여, 이동해간 지역 내에서의 인구 이동을 한층 강화시켰다. 또한 이들 이주정권들은 토착정권에 비해 영토나 토지에 대한 애착보다 호구에 대한 애착이 강하였다. 이는 수많은 인구를 대동한 채 수도를 자주 옮기고 있는 점에서 확인이 가능하다. 수도를 옮길 때마다 수많은 관료와 군대 및 상인과 수공업자 및 농민이 강제 이주당해야 했다. 정착 농경 생활을 영위하던 한족도 기온의 저하와 유목민의 남하에 대응해야 했다. 일부는 남아서 낮아진 기온에 적합한 농작물을 경작하면서 남하해온 이주정권 치하에서 살아갔다. 반면 많은 인구가 과거에 자신들이 살던 환경과 비슷한 지역을 찾아 역시 남하해갔다. 그렇게 ‘발견’된 지역이 과거 습윤하였지만 기후 변화에 따라 거주가 가능하게 된 장강 하류의 강남 지방이었다. 이주 농경민이 보유한 선진적 농법과 철제 농기구 덕분에 강남 지방은 곧 경제적으로 발전하기 시작하였고, 이주민들은 예전의 문화적 전통을 강남 지방에서도 이어갔다. 그 결과 강남 지방은 10세기 이후 경제적․문화적 중심지가 되어 오늘날에 이르게 되었다.

Before the 10th century, there were diverse factors in large-scale mobility of population in East Asia, including the political and economic factors, but the most important factor was the changing in average temperature for the year with variations of climatic change. Interdisciplinary researchers with meteorologists and climatologists, botanists, geologists and historians traced the climatic change that there were 4 times of warm era and 4 times of cold era in East Asia about 5000 years until now. In the warm era, the powers of the settled agricultural people, mainly Hanzhu(漢族), extended towards west, east and south by their military conquest and policy of deportation. In cold era, whereas, the massive northern nomadic people moved southward to conquer the settled agricultural people, and they established a lot of migrated regimes one after another, fought each other to control over the population of migrants. The main leaders of the migrated regimes who themselves were migrants also took policies of deportation moving the conquered agricultural people and nomadic people to particular area by force, strengthened the mobility of population. In addition, they were more concerned about holding of conquered populations than conquered territory or land, compared the native regimes. They didn’t mind moving of the capital, therefore many officials, military troops, merchants, craftsmen and farmer should be moved together by force whenever the migrated regimes moved of the capitals. Hanzhu, settled agricultural people, likewise had to respond the decline of the average temperature and the moving southward of the nomadic people. Some survived under the rule of migrated regimes, but the many of the people migrated southward to look for similar environment and areas they have been lived. They finally ‘discovered’ in Jiangnan(江南) region, humid regions in past, but now changed proper region to live in because of the climate change. Through their efforts to cultivate wasteland with the advanced farming and the iron agricultural tools, the economy and culture of Jiangnan region began to develop rapidly, and migrants managed to keeping up their cultural traditions. Since the 10th century, Jiangnan region hold the center of the economy and culture in East Asia even today.

Before the 10th century, there were diverse factors in large-scale mobility of population in East Asia, including the political and economic factors, but the most important factor was the changing in average temperature for the year with variations of climatic change. Interdisciplinary researchers with meteorologists and climatologists, botanists, geologists and historians traced the climatic change that there were 4 times of warm era and 4 times of cold era in East Asia about 5000 years until now. In the warm era, the powers of the settled agricultural people, mainly Hanzhu(漢族), extended towards west, east and south by their military conquest and policy of deportation. In cold era, whereas, the massive northern nomadic people moved southward to conquer the settled agricultural people, and they established a lot of migrated regimes one after another, fought each other to control over the population of migrants. The main leaders of the migrated regimes who themselves were migrants also took policies of deportation moving the conquered agricultural people and nomadic people to particular area by force, strengthened the mobility of population. In addition, they were more concerned about holding of conquered populations than conquered territory or land, compared the native regimes. They didn’t mind moving of the capital, therefore many officials, military troops, merchants, craftsmen and farmer should be moved together by force whenever the migrated regimes moved of the capitals. Hanzhu, settled agricultural people, likewise had to respond the decline of the average temperature and the moving southward of the nomadic people. Some survived under the rule of migrated regimes, but the many of the people migrated southward to look for similar environment and areas they have been lived. They finally ‘discovered’ in Jiangnan(江南) region, humid regions in past, but now changed proper region to live in because of the climate change. Through their efforts to cultivate wasteland with the advanced farming and the iron agricultural tools, the economy and culture of Jiangnan region began to develop rapidly, and migrants managed to keeping up their cultural traditions. Since the 10th century, Jiangnan region hold the center of the economy and culture in East Asia even today.

climatic change, mobility of population, warm era. cold era, migrated regime, moving of the capital