The purpose of this paper is to underline the importance of historical research for interpreting theory by presenting the author's PhD research on the role of interpreters during the negotiation of Canadian Indian treaties in the 19th century. Firstly, the relation between history and theory in translation studies is emphasized, together with the need for a socio-cultural approach in interpreting studies. History is viewed as the first stage towards a 'cultural turn' in interpreting. Secondly, the context of Canadian Indian treaties' negotiations is examined, and some details about the interpreters are provided. Interpreters belong to two groups: the Métis and the missionaries, both Catholic and Protestant. To conclude, the article proposes two hypotheses on the active role that interpreters played during these negotiations. This study aims to contribute to a better understanding of the socio-cultural dimension of interpreting, especially when great cultural and social differences separate both parties, such as in community interpreting. [Based on abstract in journal]