Richard Westmacott’s pedimental sculpture has been widely ignored or misunderstood in modern accounts of the British Museum. This article explains it for the first time in light of the sculptor’s own comments on the work, and within the context of programmatic elements on contemporary public buildings. Doing so reveals the sculpture’s allegorical narrative as representing a conservative rebuke to secular notions of human progress. Historical accounts record the survival of this interpretation for as long as Westmacott’s textual explanation was attached to the work. However, this interpretation became obscured subsequently by an antithetical definition of the word ‘civilization’. The sculptural execution is a deliberate analogue to the work’s conservative programme, embodying an imagined version of classical severity. For the stylistic conception, Westmacott drew on the work of Charles Robert Cockerell, the most notable nineteenth-century theorist of architectural sculpture.