Why, how and with what prospect of success do empires manage their distant borderlands? In times of relative calm and security these questions hardly arise: in the early eighteenth-century British governments treated their colonies, and their frontiers, with ‘salutary neglect’.By 1748, matters were dramatically different. Settler intrusion into Native American lands, apparently unfettered by provincial governments, and encouraged by speculators, combined with perceived French advances threatened to engulf the whole region in a disastrous war. Quarrelsome colonies proved unable to combine in self-defence, forcing ministers to centralise control of Indian and military policy. This programme, undertaken with inadequate resources and in the face of conflicting priorities, undermined colonial autonomy and provoked resistance and resentment. When London attempted to draw a continuous peacetime boundary between settled areas and Indian lands, the resentment became a major cause of the American Revolution.