"I invented Edna because I hated her.... I poured out my hatred of the standards of the little people of their generation."

Wrote Barry Humphries, quoted in "Barry Humphries (Dame Edna to You, Possums) Is Dead at 89/Bewigged, bejeweled and bejowled, Mr. Humphries’s creation was one of the longest-lived characters ever channeled by a single performer" (NYT).

Dame Edna emerged when the young Mr. Humphries, under the sway of Dadaism, was performing with a repertory company based at the University of Melbourne.... On long bus tours, he entertained his colleagues with the character of Mrs. Norm Everage — born Edna May Beazley in Wagga Wagga, Australia, sometime in the 1930s — an ordinary housewife who had found sudden acclaim after winning a nationwide competition, the Lovely Mother Quest. 

Unthinkable as it seems, Edna was dowdy then, given to mousy brown hair and pillbox hats. But she was already in full command of the arsenal of bourgeois bigotries that would be a hallmark of her later self...

I loved Dame Edna. (Click my "Dame Edna" tag.) But not everyone appreciated this sort of humor: 

In February 2003, writing an advice column as Dame Edna in Vanity Fair, he replied to a reader’s query about whether to learn Spanish. “Who speaks it that you are really desperate to talk to?” Dame Edna’s characteristically caustic response read. “The help? Your leaf blower? Study French or German, where there are at least a few books worth reading, or, if you’re American, try English.” 

A public furor ensued, led by the Mexican-born actress Salma Hayek, who appeared on the magazine’s cover that month. Vanity Fair discontinued Dame Edna’s column not long afterward. 

In an interview with The Times in 2004, Mr. Humphries was unrepentant. “The people I offended were minorities with no sense of humor, I fear,” he said. “When you have to explain the nature of satire to somebody, you’re fighting a losing battle.” 

Mr. Humphries drew further ire after a 2016 interview with the British newspaper The Telegraph in which he denounced political correctness as a “new puritanism.” In the same interview, he described people who transition from male to female as “mutilated” men, and Caitlyn Jenner in particular as “a publicity-seeking ratbag.” 

Here's that Telegraph piece from 7 years ago: 

[Germaine] Greer attracted fury after claiming that “trans” women such as Caitlyn Jenner (formerly the Olympic athlete Bruce Jenner) are men “who believe that they are women and have themselves castrated”, with students at Cardiff University describing Greer as “transphobic” and someone who should make all right-minded people feel “sick to [their] stomachs”.

Humphries is supportive of Greer in the controversy. “I agree with Germaine! You’re a mutilated man, that’s all,” he says. “Self-mutilation, what’s all this carry on? Caitlyn Jenner – what a publicity-seeking ratbag. It’s all given the stamp – not of respectability, but authenticity or something. If you criticise anything you’re racist or sexist or homophobic.”

Some video:

AND: Here's the London Times obituary:

During Dame Edna’s theatrical performances she would inform middle-aged women in the audience that they had no fashion sense and smelt like a week-old cleaning rag. “Tell me the story of that frock,” she would order a victim. “It’s obviously an old favourite. You were wise to remove the curtain rings.”... 

One Australian critic said that the character was so successful because she was “a perfect parody of a modern, vainglorious celebrity with a rampant ego and a strong aversion to the audience, whom celebrities pretend to love but actually, as Edna so boldly makes transparent, loathe for their cheap shoes and suburban values”. 

Dame Edna and Humphries’s boorish Sir Les Patterson, “the cultural attaché to the Court of St James’s”, who had a blotchy face, oversized dentures and rumpled, ill-fitting clothes were among the most famous theatrical Australian characters....

Audiences throughout the English-speaking world knew to avoid the front rows of his solo performances, unless they wished to risk being the recipients of Dame Edna’s sarcastic comments or Sir Les’s spittle, as he recounted his erotic adventures involving his all-too obvious “trouser snake”. Karen, his lesbian daughter, was dismissed as a “sausage dodger”..... 

Humphries never lost his passion for Dadaism: “I still consider myself to be a Dadaist and always put it down as my occupation on immigration forms — no one ever queries it.” 

In his seventies Humphries wrote his own obituary under the name of “Bronwyn Praxilities”, in which he described himself as “a self-indigent and inaudible has-been who lacked any sense of Progressive Social Relevance”....