Back in the eighteenth century, European culture was obsessed with the idea of the noble savage, particularly the Celtic variety. They loved the idea of some kilt-clad warrior striding around a misty moor or foggy fen, playing lonely bagpipes and gazing down the glen.
There was a slight problem, though: no actual account of a noble Scotsmen had ever been found*. So a wily poet called James Macpherson decided to make one up. He claimed to have discovered and translated an ancient Scots epic about a chap called Ossian. It was a complete fraud, and those parts of it that I've read are terrible, but it was the fraud that the literary world wanted, and they lapped it up.
Goethe loved it and mentioned it in Werther. Napoleon was so obsessed with the poem that he carried a copy with him everywhere. He even insisted that his godson (who later became king of Sweden) be renamed after one of the characters in the poem, who had the then obsolete moniker of Oscar.
Thus did the name Oscar suddenly become popular all over Britain and Scandinavia.
A few decades later an Irish nationalist called Jane decided to give her son the silliest possible old Celtic name she could imagine to fit in with her political principles. So she called him Oscar Fingal O'Flahertie Wills Wilde.
Oscar Wilde was convicted of Uranian lust in 1895 and the name Oscar took a bit of a hit in its popularity, but only in Britain. In Scandinavia Oscars thrived. And in Australia.
In fact, Oscar was such a common Australian name that when, in the sixties, a comedian called Ron Frazer wanted to create a character who would embody all the quintessential Australian virtues of boorishness and barflying, he called him Oscar, or more precisely he used the Australian shortening of the name: Ocker. Here is a video of Ocker in action.
As you can see Ocker isn't actually that bad a fellow. However, the word has moved on. Most Australians today are unaware of the original comedy sketches and use the word ocker (uncapitalised) as an adjective to refer to the most boorish, beer-swilling, prawn-barbying, becorked-hatted bush-whacker imaginable. It's the Australian equivalent of redneck.
It's therefore an immensely useful word if you wish to abuse Australians in words of their own invention, and who doesn't want to do that?
*This is unchanged.