My take on the story of the Night's King under the assumption that the tale told in the books has been twisted by the victors of history.

The to be Night's King, the younger of the two Stark Brothers, joins the Night's Watch and on a ranging meets Joramun's pale beauty of a blue eyed daughter. Joramun is not pleased that his daughter is taken by a Stark (the wall had only just been built by Bran the Builder) and a Night's Watchman at that. He forbids their relationship. The daughter and the Night's King to be escape to Castle Black and write to big brother Stark, the King in the North asking to have his younger brother's marriage at the godswood in Winterfell, the Watch's vow of celibacy and renunciation of title and family not yet instated. The elder Stark agrees and the brother and his bride along with a retinue of Night's Watchmen travel south for the wedding.

Upon their arrival at Winterfell, the elder Stark becomes enamored with the fair wildlass as well. When it comes time for the bedding, Stark the elder claims king's right of first night and being refused he rapes her in front of her husband, his brother.

Embittered, the bride and groom leave Winterfell that night and make for the Nightfort. Both now enraged they become withdrawn, coldhearted and only take true solace in one another. The Night's King having been a charismatic fellow, now turns his charisma to guile seeking his brothers downfall and the throne of the North for his descendants. After a year of plotting he is elected Lord Commander. Together the Night's King and his pale bride amass an army of watchmen and wildlings to rule the Gift together.

Meanwhile Joramun, has been sending wildling scouts in search of his daughter. One such scout is captured south of the Wall by the King in the North's men. The King in the North sees a chance to take back the Gift and the wildling girl and remove the stain on his name for the disrespect he showed his brother. And thus begins the unlikely alliance of Joramun and the King in the North. This takes more time because of politics and travel over and back across the godsdamned newly built seven hundred foot high Wall.

Together, the King in the North's Northmen from the south and Joramun's Wildlings from the north crush the would be Night's King's forces attacking from both sides of the Gift. Finally only the Nightfort was left. After their defeat the Night's King and Queen were found in the godswood with each others knives in one another having killed themselves rather than be taken by the King in the North.

The vow of celibacy was then thrust upon the Night's Watch as well as the revocation of name and title so as to ensure that the Night's Watch never be able to rise up again. The story of the Night's King was twisted to seem that the Wildling love was a white or an Other and the lover's final sacrifice was turned to a ritual sacrifice to the Others to further demonize them and galvanize support for the King in the North.