[1] Under the Window is considered to be one of the first earliest examples of a designer picture book,[2] and its popularity caused it to be imitated, the most blatant of which was the edition Frederick Warne published within weeks of its release.

In the late 1870s, Greenaway—who had been illustrating greeting cards—persuaded her father, who was also in the engraving business, to show Edmund Evans her manuscript, Under the Window.

[8] This appealed to the sensibilities of the time, since the children's clothing appeared sweetly old-fashioned to Greenaway's contemporaries, the more sophisticated of whom were involved in the Artistic Dress movement of the era.

[9] The book reflected the influence of the Arts and Crafts Movement with its aesthetic motifs described as "quaint fancies of olden times, soft refined colouring, and humour suggested rather than strongly expressed"[10] Each of the pages is framed with a border, creating a detached, static effect, "as if the reader were observing the scene".

[11] Other fashionable motifs illustrated in the book are sunflowers, blue and white china, and Queen Anne Style architecture.

[11] Also evident within the book is the influence of Japanese woodblocks with their definite block outline, flat, delicate colours, and use of white space.

[19][20] Frederick Locker denounced the book as "a shameful imitation of your manner, which if it goes on will tend to disgust the brutal British public and therefore injure you.