Eloise is a series of children's books written in the 1950s by Kay Thompson and illustrated by Hilary Knight.

Eloise is a young girl who lives in the "room on the tippy-top floor" of the Plaza Hotel in New York City with her nanny, her pug dog, Weenie, and her turtle, Skipperdee.

The character was developed by the author based on her childhood imaginary friend and alter ego, with a voice in which Thompson spoke throughout her life, according to her biographer, filmmaker Sam Irvin.

[2] The illustrator stated that the image for Eloise was based on one that his mother, Katherine Sturges Dodge, had painted, during the 1930s.

The same publisher began producing Eloise stories "in the style of Kay Thompson and Hilary Knight" to their early-reader Ready-to-Reads line in 2005.