Eastern Asiatic Region

The Eastern Asiatic Region (also known as Oriasiaticum, Sino-Japanese Region, East Asian Region, Temperate Eastern Region) is the richest floristic region within the Holarctic Kingdom and situated in temperate East Asia. It has been recognized as a natural floristic area since 1872 August Grisebach's volume Die Vegetation der Erde and later delineated by such geobotanists as Ludwig Diels, Adolf Engler (as Temperate Eastern region), Ronald Good (as Sino-Japanese Region) and Armen Takhtajan.

The Eastern Asiatic Region is dominated by very old lineages of gymnosperms and woody plant families and is thought to be the cradle of the Holarctic flora. Moreover, this floristic region wasn't significantly glaciated in the Pleistocene, and many relict Tertiary genera (such as Metasequoia glyptostroboides, ancestors of which were once common throughout the Northern Hemisphere up to subpolar latitudes) found refuge here.