On 1 November 1926 an Australian-led force left Rabaul bent on justice. This punitive expedition was in response to the recent killing of four Australian men in the Nakanai district of New Britain seventy miles from Rabaul. Called the Nakanai massacre, it was the bloodiest attack on whites in New Guinea for twenty years. This article explores the Nakanai massacre and examines the revealing responses to it. It argues that the Nakanai massacre generated different levels of concern and anxiety about violence on Australian frontiers than contemporary mainland massacres because it occurred within New Guinea and under the intense international scrutiny of the League of Nations. This incident not only brings to the fore public debate about what Australia's rule in New Guinea was or should be. It argues it had consequences extending to retention of this territory and Australia's national prestige in the highly charged international setting in of 1926.