This thesis focusses on the Temple of Jupiter Optimus Maximus on the Capitoline Hill in Rome. It deconstructs what is proposed as the ‘myth’ of the Archaic temple in order to argue that the sixth century structure as we understand it should be understood as an Augustan literary construct. The Augustan ideological reconstruction of the temple is closely examined to demonstrate that there was a deliberate program designed to lessen the significance of the temple within the city of Rome in the late first century BC. This myth of the Archaic temple has pervaded modern scholarship particularly in regards to the argument of the Jupiter Capitolinus’s dimensions. This is clear when reviewing the sequence of reconstructions made since the nineteenth century. The reconstructions of Einar Gjerstad, John W. Stamper, Anna Mura Sommella and the Capitoline Museums are of specific interest, and the static view of the temple as one whose form remained unchanged for a millennium is contested. In order to move away from the emphasis on the Archaic phase ofthe temple. its entire structural history is examined from the sixth century up to the Flavian rebuildings in the first century AD. This establishes a complex building whose form changed gradually over time. The most important modification was the enlargement of the temple in the form of a two room posticum added to its plan in the first century by Vespasian. This resulted in a form atypical to the canonical Tuscan temple. The substructure discerned in the most recent excavations showing this plan has been dated by Mura Sommella to the Archaic period, but it should instead be dated to the early Imperial period. This revised dating accounts for its absence in the descriptions of the Tuscan temple provided by the ancient sources.