Peoples mentioned in the Dongyi ('Eastern barbarians') section of chapter 30 of the Records of the Three Kingdoms (3rd century), plus the Chinese commanderies at the time (in purple).
Own work, using

Coastline from Natural Earth 1:10m Physical Vectors
Rivers and lakes from GSHHG
Areas from Shin,  Michael D. , ed.  (2014)  Korean History in Maps, Cambridge University Press, pp. 16, 19  ISBN:  978-1-107-09846-6.
Kanguole