Chapter 7 concludes by considering some of the book’s implications for the more recent history, and future, of linear borders. First, the way in which boundary studies has developed since the early twentieth century may help explain why boundaries have been so rarely altered or created since then. Having been further purified of its politics, boundary studies is left unable to produce reasons to change boundaries, and has become focused instead on maintenance work on existing boundaries. Second, the chapter returns to the question of natural and artificial boundaries, arguing that some ways of speaking of ‘artificial’ boundaries are more accurate than others, and that the history of linear boundaries can help us make sense of what it means to call boundaries ‘artificial’.

The second part of the book moves from the origins of linear borders to their consequences for international politics. Because linear borders are distinguished from other kinds of frontiers by certain technical practices, it is the expertise involved in these practices which forms a central part of how the linearization of borders makes a difference. Chapter 5 charts the emergence of modern boundary studies, focusing in particular on the writings of colonial surveyor Thomas Holdich, academic geographer Ellen Semple, and Viceroy of India Lord Curzon. This subfield grew partly out of a meeting between political geography and the practice of colonial surveying in the late nineteenth century. I show how boundary studies was able to give new life, for a few crucial decades, to the otherwise questionable and politicized idea of ‘natural boundaries’ as a respectable scientific concept, and argue that colonial knowledge was key to its emergence.