Portal:Australia/Anniversaries/September/September 1
- 1906 – Papua New Guinea is made an Australian protectorate.
- 1912 – The Golden Wattle is declared as Australia's national flower but only declared as Australia's official floral emblem in 1988.
- 1925 – Thomas Blamey becomes Chief Commissioner of Police in Victoria.
- 1934 – The Pyjama Girl is discovered in Albury, New South Wales.
- 1951 – The ANZUS Treaty between Australia, New Zealand and the United States is signed in San Francisco.