G4F-records, who made the sountrack for Humankind, are regularly releasing making-of videos about the sountrack. The latest: China, in total 4 videos are currently on Youtube (pre-colombian, Mongolian, European middle ages, and China). Have a look at their playlist here: https://www.youtube.com/watch?v=hSL95m_Nazg&list=PLtzah_dj5hUWd89mBtwZfSEmKjMVW3FwY&index=5
Discuss the music in our forum: https://forums.civfanatics.com/threads/humankind-music-making-of.672888/