From IGN: “When Elden Ring was first announced, one of the biggest surprises is how its a collaboration between FromSoftware and A Song of Ice and Fire author George R.R. Martin. Since then, more information about the collaboration has come to light and while Martin was responsible for creating the overall world and mythos of Elden Ring, the in-game text is being director Hidetaka Miyazaki.

In From fashion, the story is told in fragments, and we havent changed our principle of providing a world and narrative that the player can interpret for themselves, FromSofts Yasuhiro Kitao says.”

Source: N4G PC Elden Ring's In-Game Text Is Being Written by Miyazaki, Not George R.R. Martin