The White King is a character who appears in Lewis Carroll's novel Through the Looking-Glass and what Alice found there. He alongside his wife the White Queen and his daughter Lily the pawn take a journey through the land through Alice's adventures in the looking-glass world, unaware that Alice is watching them.
The White King was shown playing a game of chess with his family and asking his army soldiers to help Humpty Dumpty after Alice knocked him over and he rolled over off the chessboard and he was still on the board with his family.
Will Scarlet is taking the place of the White King after he was freed from the genie lamp and he kissed Anastasia the Red Queen and he broke the spell that Jafar placed on her after making her fall in love with him. That was after the lovers came to Wonderland until Anastasia's mother wouldn't let her date him because he was a thief. They got married soon after they went to Alice's wedding and Alice stated in her book that they lived happily ever after alongside The Red Queen who is now taking place of The White Queen. His background story is that the Queen of Hearts ripped out his heart and took it away from him when he became a Knave of Hearts to her, he was forced to serve her. Anastasia was forced to marry the Red King after he was engaged to her, but Will Scarlet and Anastasia were still in love.