This article considers the concepts of statehood, sovereignty, independence and international legal personality as they applied to Australia in the early years after federation in 1901. It outlines the reasons for, and the process of, federation, and charts the subsequent uneven growth in autonomy in matters of foreign relations granted by the United Kingdom. One of the clearest manifestations of such autonomy is the power to enter into treaties, and the development of this power is therefore described in some detail. The precise international legal status of Australia and the other British Dominions in the early part of the 20th century was a mystery to most legal commentators; this uncertainty was compounded by the rapidity of constitutional change within the Empire, particularly in the 1920s, and by Australia’s preference for Imperial unity over independence. For these reasons, few writers have suggested when, specifically, Australia acquired international legal personality. This article argues that, since international legal personality is a flexible rather than absolute concept, the relevant inquiry is not as to when Australia gained full international legal personality, tantamount to independence, but rather when it acquired a sufficient degree of international legal personality to enter into relations with other states, and generally to conduct itself on the international plane, had it chosen to do so. It concludes that this occurred in 1923.