After "
Hardhome" aired and Weiss and Benioff first referred to the character as the Night King,
Game of Thrones Wiki contacted
George R.R. Martin asking how to treat the White Walker referred to as the "Night King" relative to the ancient Lord Commander known as the "Night's King" - if they are the same character, or if "Night's King" is a
title that can be held by different characters, like "King in the North." He was also asked if it was significant that Benioff and Weiss refer to him as the "Night King", without a possessive "S".
Martin cryptically avoided the first question, but said he prefers the spelling "Night's King":
"As for the Night's King (the form I prefer), in the books he is a legendary figure, akin to Lann the Clever and Brandon the Builder, and no more likely to have survived to the present day than they have."[15]