This thesis will explore the material construction of the noble form in the sixteenth and early seventeenth-century Habsburg Netherlands. Understandings of substance and social structures of privilege were in potent and synchronized flux during this era and Flemish noble families, such as the Arenberg clan, were required to consistently reformulate and assert their authority. The Arenberg family were powerful and socially prominent figures in the Low Countries at this time. They were staunch Catholics and active members of the Brussels court but also engaged regularly with the commercial elites of the Northern Provinces. Structured around five case studies, the investigation will focus on the nature of different media and how the particularities of each substance were deliberately co-opted into the production of social authority. It will examine how corporal encounter with textiles, glass, paper, and pigment formulated noble honour, negotiated change, produced relationships between diverse groups, and situated the family within an ever-shifting social environment. Each chapter examines a material artefact commissioned by the dynasty at a site of contest or transformation, a situation in which the privileged nature of the Arenberg clan required consolidation or reassertion. This thesis will contribute towards a growing field of study on the Early Modern Habsburg Netherlands. It will prioritise material processes in an attempt to highlight the value of substance as a methodological tool useful for research into the fields of Catholic Europe court history currently dominated by archival approaches.