This research paper investigates how urbanization shaped a shared Roman identity across the diverse Roman Empire. Focusing on western cities like Pompeii and Mérida, it explores how urban features and economic opportunities fostered a cohesive "Romanness" among varied ethnic groups. The study examines the influence of elite-driven building projects, Roman architecture, and urban planning, while considering the geopolitical context. By analyzing the interplay of physical structures and economic dynamics, it highlights urbanization’s role in forming a collective identity, offering insights into cultural identity development in ancient societies.