Federalism is usually described in Australian political science and history as representing one, coherent amalgam of ideas, first enunciated in Australia in the 1840s-1850s. At the same time, Australia experiences ongoing debate about the wisdom and applicability of federal ideas in their present geographic form, suggesting schisms not simply within Australian politics but within federalism itself, sufficiently deep to require a reconsideration of current federalist orthodoxy. This paper seeks to reopen debate about the origins and diversity of federal ideas in Australia by squarely attacking orthodox assumptions regarding their historical starting point and subsequent hegemonic character. The territorial separation of Van Diemen's Land from New South Wales in 1823-1825, the foundation of Port Phillip in 1835-1841 and other events reflected a significantly earlier reception of federal thought into Australia than previously described. Sometimes hinted at, but hitherto not analysed, this first federalism had a previously unappreciated level of support in British colonial policy and drew directly on Benjamin Franklin's 'commonwealth for increase' ideas of territorial change booming in America. While these discoveries entrench notions of the suitability of federalism in Australia, this original Australian federalism was quite different to the 'classic' or compact theory of federalism dominating Sydney and London ideas of the 1840s-1850s, the 1890s and the bulk of 20th century scholarship. In fact Australian political thought contains not one, but at least two quite distinguishable and sometimes conflicting ideas of federalism. By recognising Australia's first, more decentralist version of federal principle, the paper emphasises Australia's uniqueness in global history, exposes as a myth the assumption that Australian federalism grew purely out of a landscape of autonomous Australian colonial governments, and reveals that most colonies were formed in circumstances which presumed their long-term role as subnational units in a continental federation. This reappraisal of federalism's roots helps explain longstanding dissent over the territorial basis of Australian constitutionalism and aids the potential for a new reconciliation of federalism and regionalism in Australian political thought.