After World War I and the Ottoman Empire’s dissolution, Greece engaged in the Asia Minor Campaign (1919–1922). Refugee inflow to Greece, already significant before these events, surged dramatically after the Catastrophe of Smyrna in 1922. The compulsory population exchange between Greece and Turkey, mandated by the Treaty of Lausanne in 1923, further necessitated rapid and effective housing solutions. The League of Nations established the Refugee Settlement Commission (RSC) to manage permanent accommodation. Urban refugee settlements were created throughout Greece, introducing new urban planning systems and reshaping the urban landscape. The refugee houses were based on typical plans and mass-produced, either by external contractors or by the refugees themselves. RSC engineers applied a series of building types to provide efficient, scalable, and sustainable solutions, ranging from simple wooden or mudbrick structures to more elaborate dwellings and even apartment blocks. This study delves into the architectural and urban planning strategies employed by the Greek government and international organisations, emphasizing modularity and standardization. Through a detailed analysis of the design frameworks, construction methodologies, and material usage, this paper explores how these principles facilitated the swift creation of functional and cohesive refugee communities. Case studies from key settlement areas (such as Xanthi and Kavala) are presented to illustrate the practical application and outcomes of these strategies. The findings reveal that the emphasis on modular and standardized designs not only expedited the construction process but also laid the foundation for the development of resilient and adaptable urban environments. This research contributes to the broader understanding of emergency urban planning and offers valuable lessons for contemporary refugee housing initiatives.