Federalism is usually described in political science as a single body of ideas-in Australia's case arriving in the 1840s-50s and moving to constitutional reality in the 1890s. This article re-examines the origins and diversity of federal ideas in Australia. It suggests that federal thought began influencing Australia's constitutional development significantly earlier than previously described. This first Australian federalism had a previously unappreciated level of support in British colonial policy and drew on Benjamin Franklin's American model of territorial change as a 'commonwealth for increase'. The revised picture entrenches the notion of federalism's logic but also reveals a dynamic, decentralist style of federalism quite different from Australia's orthodox 'classic' or compact federal theory. In fact, Australian political thought contains two often-conflicting ideas of federalism. The presence of these approaches helps explain longstanding dissent over the regional foundations of Australian constitutionalism.