Frequent commenter Paul sent me a link to this OED essay by Bruce Moore, director of the Australian National Dictionary Centre at Australian National University, on “Australian English in the twentieth century.” It’s full of interesting facts; here’s the section on the history of the tripartite division of accents:
And then, at the end of the nineteenth century, something curious and largely unpredictable happened to Australian English. In response to a newly-developed concept of Received Pronunciation in Britain, which was closely tied to notions of social prestige, some Australian speakers modified their vowels and diphthongs in order to move them towards the British exemplars. From the 1890s, and well into the 1950s, elocution was in the air, and elocution teachers found a ready market for the teaching of British vowels and diphthongs to the socially-aspirational classes. This modified form of Australian speech came to be called Cultivated Australian.
As if in response against this new British-based Cultivated Australian, a diametrically opposed form of Australian English developed in the first part of the twentieth century. This form moved the Australian vowels and diphthongs even further away from what was now the British standard of pronunciation, and emphasized nasality, flatness of intonation, and the elision of syllables.This second modified form of Australian speech came to be called Broad Australian. While it is true that when non-Australians hear any Australian say ‘mate’ or ‘race’ they are likely to mistake the words for ‘mite’ and ‘rice’, the mishearing is most likely to occur with speakers of Broad Australian.
The majority of Australians continued to speak with the accent that had been established in the first fifty years of settlement, and this form of speech came to be known as General Australian. General Australian was now book-ended by Cultivated Australian and Broad Australian, and these forms of Australian English came to carry with them very different sets of values. Cultivated Australian, for example, came to express a longing for British values and a nostalgia for a country that was still regarded by many as ‘home’. Broad Australian was strongly nationalistic, and carried with it notions of egalitarianism that were antagonistic to a perceived class-obsessed and hierarchical Britain. …
In the second half of the twentieth century… Australian English became ‘naturalized’ in its own country, its accent and vocabulary were accepted as a national norm, and it was celebrated in such works as the Australian National Dictionary of 1988. In the first half of the twentieth century Cultivated Australian had been the socially prestigious accent; by the end of the century its utterance was likely to generate derision and laughter. As a result, Broad Australian, too, has been in decline, as if this extreme form was no longer required now that the imperial elements were dead. General Australian is now to the fore—as it had been before the false dawns of Cultivated and Broad.