The rulers of great empires tend to lavish special attention on their capitals. By shaping the fabric of urban life at the center of power, they can advertise the achievements on which their authority is founded, stake out the core values they claim to represent, and generally demonstrate the benefits that accrue from their control over the state. As Suetonius recognized, Augustus was the first to endow Rome with an ornamental splendor that accorded with the majesty of its empire, so much that he rightly could have claimed to have taken over a city of brick and left one of marble (Suet. Aug. 28.3; cf. Tac. Ann. 1.9.5). Contemporary scholarship is solid in its embrace of this assessment, with multiple studies demonstrating how Rome was transformed into a vehicle for a new Imperial ideology in the Augustan age (Haselberger 2007, Rehak 2006, Favro 2005). Although no one should doubt the profound impact of monarchy on Rome's monumental and administrative character, a reign-by-reign approach to the study of the city's development under the Caesars imposes certain limitations that need to be acknowledged. Unlike Persepolis or Khanbalikh, Rome was not a new foundation when it became the seat of imperial authority, much less when it fell under monarchical control. As such, the city did not offer a blank canvas upon which a ruler could project a discrete vision of his power. Indeed, Augustus was particularly adept at incorporating existing urban features into his new, marble Rome. For * Published in A. Zissos (ed.), A Companion to the Flavian Age of Imperial Rome. (Malden, MA: Blackwell, 2016). example, he made sure that an ancient thatched hut, touted as the "house of Romulus" (casa Romuli), was assiduously maintained on the slope of the Palatine, not far from his own residence and the gleaming temple of Apollo he built next door (Dion. Hal. Ant. 1.79.11). For later emperors, the challenge of dealing with a preexisting urban landscape encompassed not just monuments hallowed by antiquity, but the interventions of their predecessors as well. Within the richly layered landscape of Imperial Rome, novelty, however significant, would always be seen as part of a continuum. The greatest drawback to a discussion of Rome's urban development organized according to the reigns of successive emperors is that it may obscure the importance of overlap between them. It was not uncommon for a project conceived under one emperor to be completed by another. The Flavian Amphitheater (Colosseum), which was begun during Vespasian's reign but inaugurated by Titus and only fully completed under Domitian, is a classic example. While we can still safely describe this monument as "Flavian," we are on less solid footing with a monumental complex such as the one begun under Domitian but dedicated after his assassination as the Forum of Nerva (Suet. Dom. 5). Scholars who emphasize links between the architectonic decoration of this structure and the policies of the emperor in whose reign it originated may choose to promote the late antique nickname "For...