The call-out sparked a massive response for its day – more than 32,000 entries (the population back then was 3.8 million).
The joint winning entries were all remarkably similar to what the Australian flag looks like today.
The five winners were:
Annie Dorrington, a well-known artist from Perth.
Ivor Evans, a 14-year-old Melbourne schoolboy whose father owned a flag-making business.
Lesley Hawkins, an 18 year old from Sydney;
Egbert Nutall, an architect from Melbourne.
William Stevens, a first officer with the Union Steamship Company of New Zealand.
The winners received £40 each from a total prize pool of £200 (about $30,000 in today’s money).
King Edward VII approved two designs for the flag in 1903: the Commonwealth blue design (national flag), and the Commonwealth red ensign for the merchant Navy.
But people were confused about which flag was which, with the red flag being used on land.
So in 1941, Prime Minister Robert Menzies recommended that the blue flag be the national emblem. Subsequently, the Flags Act of 1953 proclaimed that it be so.
While there has been some debate over revamping the Australian flag, such a procedure would not happen without a referendum: an amendment to the Flags Act was passed in 1998 to ensure that the Australian flag could only be changed with the consent of the Australian public.
Other official flags in Australian include the Australian Aboriginal flag, the Torres Strait Islander flag and the flags of the Australian Defence Force.