This paper explores the issue of colonial borders through a case study of the intra-imperial boundary between Tunisia and Algeria, two territories under French rule between 1881 and the first decade of the twentieth century. The aim here is to understand what was at stake when it came to separating two territories holding different legal status but both administered by the French: Algeria which had officially become a French colony in 1830 and Tunisia which was given Protectorate status in 1880. The paper considers some of the many disputes over the border that took place both in the field and in colonial administrative offices. It also raises the question of the scope of colonial rule by exploring the way the border was never fully determined and was constantly redrawn by the inhabitants of the border regions themselves, who were presented first as tribes, and later, as either Algerian or Tunisian by the French civil and military administrations, and by the political authorities in Algiers, Tunis or Paris. As they all had their own interests in the matter, disputes were common but were also sometimes resolved in unexpected ways. Finally, the paper raises a further issue concerning the question of national identity in the context of the definition of national territories, which reveals the full ambiguity of the concept of identity in the colonial situation
