 The most populous region of China was southern China after the depopulation of the north and the migration of northern Chinese to southern China.Different waves of migration of aristocratic Chinese from northern China to the south at different times resulted in distinct groups of lineages, with some lineages arriving in the 300s-400s and others in the 800s-900s.The Eastern Jin recovered its unity in the face of the 383 invasion by the Former Qin.