Historians studying the transfer of artistic ideas across the Pyrenees during the 11th and 12th centuries habitually return to the same phenomena to describe how and why ideas travelled – most notably pilgrimage and monasticism. While it is undeniable that both played significant roles in facilitating the movement of artists, they were not the only forces that enabled creative connections. The late 11th and 12th centuries in Aragon, for example, saw the kingdom’s transformation into a major participant in the Christian conquest of Iberia. The settlement and urbanization of the growing kingdom undertaken during this period demanded church building on a wide scale. In light of this, the linked phenomena of migration and urbanization also should be considered as major factors in the transfer of artistic ideas. In this paper, I present an instance of transregional cooperation at the worksite of Santa María de Uncastillo (Zaragoza), carried out by stone sculptors trained on either side of the Pyrenees, as the product of both urbanization and migration. On the one hand, the demands of urbanization brought about the project upon which the various sculptors collaborated. On the other, the sculptors themselves were migrants – and perhaps eventually settlers – whose collaboration enacted on a small scale the broader goals of urbanization throughout the kingdom.