This thesis analyses the different routes for ethnicity (re)creation pursued by the Mapuche diaspora living in Santiago de Chile within the margins of indigenous associations framed by the urban milieu since the recovery of democracy in the early 1990s. Through the analysis of Mapuche and non-Mapuche literature, this thesis examines the longstanding consequences of colonisation, in which traditional socio-political forms of organising have been subject to profound transformations. References to a former rural life, framed by images of the homeland, the Ngulumapu, are key in the understanding of associational participation in the city. From a theoretical perspective, this thesis presents ethnicity as a dynamic social construct that encourages the Mapuche to create and join associations in a predominantly non-indigenous urban milieu. Despite the inclination of the Mapuche to understand ethnic characteristics through primordial lenses, this study reveals that these perceived fixities are a matter of construction for which social interactions are crucial. While bounded by the margins of the Chilean nation-state, the Mapuche in Santiago are introduced as a category of diaspora to understand how the sense of belonging and attachment to their homeland plays a key role for voluntary associational development. Based on the information gathered through an eight-month period of ethnographic fieldwork, this thesis discusses the different ways in which the Mapuche members of indigenous associations manifest their concerns about the meaning of being – or not being – a true Mapuche and investigates how identity classifications impact the collective (re)construction of their ethnicity in the city. This thesis then provides an examination of the ways in which the Mapuche have been engaged in searching for space in which to develop ethnic-based activities such as workshops and traditional ceremonies. As a result of the repeated use of space over time for ethnic-based activities, Mapuche members of associations gradually undertake a re-signification of urban space. This leads individuals to confer meanings onto space based on a social construction of the homeland, transforming its materiality into what is presented as a symbolically-based ‘ethnic place’. This thesis also explores the (re)construction of ethnicity through collective engagement in practices considered to be emblematic of a shared identity. Finally, based on the narratives of Mapuche and public officials working in urban indigenous affairs, this thesis discusses the different methods of interaction with the state at the local, regional, and national levels for which the role of female Mapuche leaders has been fundamental. Based on the lived experiences, narratives, imaginaries, and memories shaped by social interactions, the thesis presents the Mapuche population in Santiago as a multifaceted indigenous people who struggles to collectively maintain salient ethnic traits in an urban diasporic setting.