The introduction of steam not only enhanced Australia’s transport links within the empire. It also altered attitudes towards the feasibility and desirability of transpacific connectivities, and brought new prominence to the Pacific-orientations of Australia’s eastern colonies. By envisioning steam-age connections across the Pacific, first to Panama and then to San Francisco, Australia sought to imagine and situate itself in a transpacific sphere. The routes shaped cultural sensibilities and political ideologies across the Pacific, expressed in affinities and allegiances between Australia and North America. This article examines transpacific steam from the mid- to the late nineteenth century, a fractured and indeterminate period which nevertheless laid the ground for Australia’s sense of itself as an autonomous white nation, relating across the Pacific and within a wider Anglo world beyond Britain and empire.