In Australia’s first five decades as a Federation, tax reform efforts were driven by the need to establish robust revenue bases for a growing nation and settle relative taxing responsibilities of the Commonwealth and state governments. These decades were also a time of crises with two world wars and a depression, these events being catalysts for tax and welfare reforms and influencers of the nature and extent of government in Australia.

The Constitution gave the Commonwealth exclusive access to customs and excise duties but other taxes were open to both levels of government and they soon found themselves in competition. That competition became most intense over income tax with efforts to resolve this being the focus of royal commissions into taxation in 1920–23 and 1932–34, then ultimately the 1942 Commonwealth takeover of income tax. This paper tracks those developments.