This study examines the centralization and territorialization of state power in early China by analyzing the long-term developments in the sociopolitical structures, spatial organization, and political economy of the Qi 齊 state in present-day Shandong Province. It argues that the rise of the centralized and autocratic territorial states of Warring States China (453–221 BCE) was underpinned by the emergence of a particular matrix of sociopolitical and economic institutions that were, in a departure from the lineage- and kin-based power structures prevalent in the early first millennium BCE, predicated on certain principles of territoriality including direct infrastructural and administrative control over lands, populations, and resources. To demonstrate this shift, this study synthesizes a wide range of paleographic, archaeological, received textual, and numismatic evidence to offer a fundamental reassessment of the spatial and institutional dynamics of state power in Qi over the course of the first millennium BCE. Chapter 1 broadly examines the longue durée changes in the organization of the power structures and state institutions most prevalent across the Zhou world. It focuses especially on two main institutions: (1) the Zhou lineage system upon which the sociopolitical order of the Zhou ecumene was based until it lapsed into obsolescence toward the final few centuries of the Zhou period, and (2) the land tenure systems based upon the Zhou lineage order that correspondingly transitioned from one in which state lands were partitioned on the basis of aristocratic lineage settlements to one in which they were centrally reorganized into standardized and multi-tiered territorial-administrative units. Chapter 2 interrogates bronze inscriptions, archaeological data, and received texts to establish the geographic parameters of Qi territorial expansion from the initial Qi core region in present-day Zibo first across northern Shandong and then eventually into adjacent regions in eastern and southern Shandong. It identifies a notable shift in the strategies employed to incorporate Qi’s newly conquered territories around the sixth century BCE whereby instead of appropriating existing local kin-based power networks, Qi rulers began to implement more centralized and direct administrative control. Moreover, this chapter charts the long-term political, administrative, and spatial construction of Qi’s southern frontier in the late Spring and Autumn and early Warring States periods, the figurative and literal capstone of which was the construction of the Long Wall of Qi in the late fifth century BCE. Chapters 3 and 4 further scrutinize the territorial and administrative centralization of Qi by analyzing the internal institutional developments that occurred in Qi in parallel to its external wars of conquest. Chapter 3 investigates how the destructive internecine conflicts between Qi’s elite lineages fundamentally reshaped traditional lineage-based power networks in the state and enabled the consolidation of autocratic rulership, which the Chen lineage ultimately usurped from the old ruling house of Qi in the Warring States period. Chapter 4 examines concomitant developments in the structure of Qi officialdom, military organization, and territorial administration especially of the metropolitan region centered on the Qi capital city of Linzi by analyzing bronze and pottery inscriptions and the archaeological evidence for Linzi. Finally, chapter 5 investigates the relationship between the economic integration of northern Shandong and the centralization of state power in Qi by analyzing the evidence for salt production on the Laizhou Bay coast and the circulation of Qi knife coins to reconstruct the political economic networks of the region. This analysis suggests that state-led production and distribution of key economic resources facilitated the territorial and administrative integration of the Qi state in the Warring States period, thereby shaping Qi into a cohesive political space.