John Dunmore Lang, the Scottish Presbyterian clergyman who settled in Sydney in 1823, until his death in 1878 played an important role in the religious, political and cultural life of New South Wales and helped to create two new colonies: Victoria and Queensland. His writings as much as his political and educational activities significantly contributed to the rise of early Australian nationalism. Lang envisaged a great future of a federal Australian republic – the United Provinces of Australia. Drawing on Lang’s books, pamphlets and his articles and speeches published in the colonial and metropolitan press, this paper analyses the religious, ideological, political and economic ideas that led him to present and espouse the cause of the future America of the Southern Hemisphere. The focus is on the fundamental political and social principles on which Lang wanted to establish the independent Australian nation. The paper also discusses planned political institutions, as well as expected or desired social and economic characteristics.