Australian policy relating to the United Nations falls into two well-marked periods. The first is that of the Labour Governments of Mr. John Curtin and Mr. J. B. Chifley, from the Dumbarton Oaks Conference of October 1944, when the foundations of the United Nations Organisation were laid, until the defeat of the federal Labour Government at the general election of December 1949; throughout that period, Dr. H. V. Evatt was Minister for External Affairs. The second period is from December 1949 until the time of writing (April 1956), when a coalition Government of the Liberal and Country parties has been in power under Mr. R. G. Menzies as Prime Minister; until May 1951, the Minister for External Affairs of that Government was Mr. (later Sir) Percy Spender, and subsequently it has been Mr. R. G. Casey, but Sir Percy Spender resigned from the Government only to become, for the rest of the period, Australian Ambassador in Washington and a frequent member, often leader, of Australian delegations to the United Nations.