Using the French philosopher Ernest Renan's dictum that the "nation's existence is ... a daily plebiscite" as an ironic point of departure, this dissertation examines the contours of oppositional political culture to the French annexation of the County of Nice and the Duchy of Savoy in 1860. Ceded by treaty to France by the northern Italian kingdom of Piedmont-Sardinia, these two mountainous border territories had long been culturally and geo-strategically in the French orbit. Unlike their counterparts in any other province of France, the inhabitants of the two territories were asked to approve or reject the annexation treaty, and thus their incorporation into France, in a plebiscite employing universal male suffrage. The 1860 annexation has traditionally been viewed as a rare example of an uncontroversial nineteenth-century territorial realignment, an instance where French strategic and diplomatic interests aligned perfectly with the national aspirations of the inhabitants. In fact, the annexation was always more controversial than the virtually unanimous plebiscite results indicate. The archival record shows surprisingly strong and long-lived resistance to the settlement of 1860 in both territories. Cultural tensions between French administrators and the annexed populations exacerbated separatist sentiment as the gulf between the expectations of an easy transition and the far more complex reality of the enormous administrative transformation became increasingly manifest. Unsettled and antagonistic diplomatic relationships with Switzerland (which felt entitled to territorial compensations in Savoy) and Italy (where many nationalists resented having to give up Nice) contributed to French fears that these neighboring countries would try to subvert the annexation. French administrators consistently turned to the quasi-mythical notion of "Swiss agents" or "Italian subverters" to explain the resistance that they encountered to French rule. These tensions resulted in the emergence of anti-French movements, oriented in Savoy toward nearby Switzerland and in Nice toward the newly-unified Italy. The opposition in Savoy was predominantly political and republican in character. Attracted to Switzerland's decentralized government and political liberties, it grew stronger in the 1860's as opposition to the Second Empire increased. Niçois opposition, by contrast, maintained an essentially ethno-national-territorial agenda oriented towards Italy, and had great affinities to the irredentism of Italian nationalists after 1861. The catastrophic Franco-Prussian War of 1870-1871 brought these movements to a head. Fears that Savoy and Nice might voluntarily detach themselves from the French state appeared very quickly after the Sedan disaster, culminating in street riots in Nice and the election of three separatist deputies to the National Assembly, and a movement in the northern Savoy in favor of inviting Switzerland to occupy and annex territory in the Haute-Savoie. In both provinces, separatism drew strength from the unresolved tensions of the annexation as well as from the uncertain political climate of France's Third Republic. As monarchists and republicans battled for control of the state, separatism became linked to the national political struggle. Initially this was most evident in Savoy, where the pro-Swiss separatist current in Savoy remained grounded in the area's precocious republicanism. In Nice separatism maintained its Italian dimension, but gradually became marginalized and discredited when separatist leaders became involved with the conservatives. The firm establishment of the Republic by 1880 thus, paradoxically, helped to neutralize both separatist currents and finally cemented the annexation that had occurred two decades earlier.