hi! there's a section in the FAQ on this, although it focuses on American accents ~

• American and British accents

as for Australian (and others), here are some more:

• In the year 1900 how easily would an "average" Briton be able to recognise an American, Australian, South African etc accent? Would they know they were from abroad?

• How did American and Australian accents develop into their modern forms from their British origins?

• Why do Oceanian accents sound closer to British than North American ones?

• How did the Australian accent become so differentiated from a typical English accent?

• Is the American and Canadian accent the original British accent?