Edward Hicks painted many versions of The Peaceable Kingdom, taking the theme from a passage from the Book of Isaiah, 11:6-8, which tells of all the animals gathering together in harmony. Hicks recast the Biblical text as a poem:
The wolf did with the lambkin dwell in peace
His grim carnivorous nature there did cease
The leopard with the harmless kid laid down
And not one savage beast was seen to frown.
The lion with the fatling on did move
A little child was leading them in love.
Painted late in Hicks's career, this version of The Peaceable Kingdom shows the mature artist's sensitivity to the natural world and his confident depiction of the familiar Pennsylvania landscape. Earlier versions were emblematic assemblages of animals and landscape elements, but here Hicks favored a naturalistic approach. He chose a placid horizontal format, emphasizing the unusually quiet mood of the painting. Even the anthropomorphic expressions of the animals—particularly the leopard, which may be a self-portrait—project a gentle air, replacing the intensity of earlier versions of the subject. In this late period, Hicks has a confident touch in depicting spatial recession and atmospheric effects. The landscape dominates the figures, their interlocking forms placed in triangular groupings within a broad plane that crosses the composition. Soft light plays over the forms, unifying them and blending into the background mists that permeate the scene and underscore the pictorial harmony of Hicks's painting.
Hicks often incorporated forms from popular graphic illustrations into his compositions: the grouping of the lioness with her playful cubs, the torque of the bear's head, the commanding stance of the lion, and the view of the Delaware Water Gap closing off the background are direct quotations from contemporary prints, as is the scene of William Penn signing his treaty with the Indians, another allusion to the theme of peace and harmony.