AC/DC are as good an example of the changing face of Australia in the second half of the 20th century as any restaurant, coffee bar or car dealer's yard. They went from tolerated foreigners to intrinsically local to confident overseas explorers to internationalists whose connection to Australia seemed almost irrelevant, until it mattered more than anything.

When it comes to music - don't tell the ''stop-the-boats'' lot this - migrant kids built Australian rock'n'roll. From the hostels of Adelaide to Villawood's Quonset huts, Scottish, Dutch, English and Irish kids formed bands including the Twilights, the Aztecs and the Easybeats and at first mimicked the sounds they had brought with them before making their own music.

The powerhouse in the Easybeats, writing firstly with English migrant Stevie Wright and then Dutchman Harry Vanda, was Glaswegian George Young. His younger brothers Malcolm and Angus were no less obsessed with music and after a couple of attempts formed AC/DC in 1973.

They were not cool these Sydney suburban boys who played the kind of rock'n'roll Chuck Berry would recognise. They didn't try to play complex changes and windy solos like the prog-rock crowd. They didn't touch twangy Americana like the country rock groups and they had no time for the personal and intimate confessions of the rising singer-songwriters.

And they didn't do nancy boy flash either. They eschewed the prevailing look of satin and stack heels for denim and T-shirts, their one concession to glamour a comic outfitting in a schoolboy outfit of the diminutive Angus (who in truth was no smaller than his brothers, all of them short and tiny framed).

This aversion to even a hint of glam rock was often cited as one of the reasons for the ejection of original vocalist Dave Evans and his replacement by another Scottish-born musician, the gap-toothed young veteran Bon (Ronald) Scott.

With Scott, who took over the lyric writing, they had an almost comically priapic frontman who somehow still charmed and a looked like a tough bruiser who could handle himself in a brawl if he didn't take the piss out of you first. It was one of the great tragedies of this band that just as they seemed poised to build on the US top-20 album Highway To Hell, Scott died. But it was one of the great triumphs of AC/DC that instead of folding they brought in another singer, Brian Johnson who didn't look or sound like Scott or have his wit but connected them to something even more basic and straightforward.

Johnson's first album with the Young brothers was Back In Black, which has sold more than 20 million copies.

The band simplified even further on stage and on record and the almost brutal effectiveness of this simplicity translated around the world in a way no Air Supply or INXS or Kylie Minogue ever would or could. It's no surprise to hear they've sold more than 200 million albums in 40 years. That's probably more than just about every Australian act put together.

There was even a range of Australian wines bottled under their name in recent years. Though you might say there was something very AC/DC about the fact that taste-wise, the plonk - and surely an AC/DC fan would call it plonk - might well send you back to beer.

Basing themselves in Europe, fronted by an Englishman and playing American rock, the band were often not even recognised as Australian by their fans in Brazil or Iraq or St Louis, Missouri.

In 1988 they were inducted into the Australian Recording Industry Association Hall of Fame, an industry in part built by them - and their brother, who with Vanda seemingly had written for, produced or discovered every second successful act of the 1970s and '80s pub rock scene - and forever grateful. And just a little bit yearning for their return.

That said, through the 1990s AC/DC didn't always sell new songs in the same quantities - even if the new songs often didn't sound that different to the old songs - but their tours became guaranteed moneyspinners. Their last world tour, which ran between 2008 and 2010, reportedly played to almost 5 million people and grossed more than $450 million.

It was about then though that stories began emerging of the Young brothers being seen in Australia more, of properties purchased and maybe even a permanent move back here.

There were stories, too, of ill health and closer connections sought with family. It is possibly an Australian end to a very 20th century Australian story.