 From 1911 to 1956, schools in South Australia were required to fly the Union Jack for the "national salute".In 1953, the Australian blue ensign was named the national flag of Australia, through the "Flags Act 1953".Although the Australian blue ensign replaced the Union Jack as the flag of Australia, Australian prime minister Robert Menzies reassured Australians that the Union Flag would be flown together with the Australian national flag "on notable occasions".