In his paintings from the early 1950s, Bacon engaged in complex experiments with pictorial space. He started to depict specific details in the backgrounds of these works and created a nuanced interaction between subject and setting. Figures are boxed into cage-like structures, delineated space-frames and hexagonal ground planes, confining them within a tense psychological zone. In 1952 he described this as opening up areas of feeling rather than merely an illustration of an object.
Through his technique of shuttering with vertical lines of paint that merge the foreground and background, Bacon held the figure and the setting together within the picture surface, with neither taking precedence in what he called an attempt to lift the image outside of its natural environment.
A theme that emerged in the 1950s was the extended series of variants of Velázquez’s Portrait of Pope Innocent X 1650, a work Bacon knew only from illustrations. He used this source to expose the insecurities of the powerful – represented most often in the scream of the caged figure. Through the open mouth he examined the tension between the interior of the body and the spaces of its location, which is explored more explicitly in the vulnerability of the ape-like nudes.