https://www.polygon.com/e3/2018/6/12/17453618/sekiro-shadows-die-twice-story-characters-enemy

Sekiro: Shadows Die Twice was unveiled this week at E3 in Los Angeles. It’s by FromSoftware, the same team behind the Dark Souls series and Bloodborne. But, while those games had opaque roots in fantasy and horror, Sekiro draws its inspiration from historical Japan.

In a private, behind-closed-doors viewing of the game ahead of its announcement, representatives of FromSoftware told Polygon that their game was inspired by 1500s Japan. That period of Japanese history is known as the Sengoku period, also referred to as the Age of Warring States. It was a time marked by near constant warfare which embroiled the entire region in massive political upheaval.