It’s been 30 years since “Maurice,” the Merchant-Ivory adaptation of E.M. Forster’s posthumously published novel of gay love, made its theatrical debut.

A lot has happened across that time span, not the least of it being the rapid gains LGBT rights have made, climaxed by the U.S. Supreme Court’s approval of same-sex marriage. Two entire generations of gay men suffered the ravages of a deadly AIDS epidemic. In that context, it is striking to see the film again, given all we have achieved since its release.

On the screen many gay love stories have come in “Maurice’s” wake, the most famous being the closeted sheepherder saga “Brokeback Mountain” (2005). But that was a gay love story with an unhappy ending. Those with happy ones like “Maurice” include “Beautiful Thing” (1996), a tale of gay lower middle-class British teenagers, and “Weekend” (2011), about an adult pair of British bohemians. But none have quite the special charge of “Maurice,” stemming from its lush setting and aristocratic-commoner breeding.

E.M. Forster (1879-1970) has long been acknowledged as one of Great Britain’s greatest writers. But he was largely the subject of academic study until the 1980s, when film adaptations of his work made him popular.

David Lean’s opulent adaptation of his best-known work, “A Passage to India,” was a considerable success in 1984. It was followed in 1985 by Merchant-Ivory’s far more modestly scaled adaptation of “A Room with a View.” Both “Passage” and “Room” deal with sexual awakening — producing dire results in the former but highly copasetic ones in the latter. The sight of Lucy Honeychurch (Helena Bonham Carter) suddenly kissed in a sun-drenched field in Italy by a rakishly handsome youth (Julian Sands), proved especially popular below the Mason-Dixon line where bevies of proper “Southern Belles” longed to be likewise ravished.

Beautifully made, perfectly paced and delightfully acted, “Room” was an enormous success.

But Merchant-Ivory’s next Forster step would be “Maurice,” a love story of a far more intense stripe.

Forster was an intimate friend with the radical and openly gay poet Edward Carpenter, whose life in the English countryside was completely removed from the world Forster resided in. Carpenter and his lover, George Merrill were an inspiration for the book. But the saga of “Maurice” largely reflects Forster’s own life and frustration with his class — Carpenter’s counter-example coming into view only at the novel’s end.

Originally written in 1914, then revised in 1932 and again in 1960, “Maurice” was shown by Forster only to select friends, including Christopher Isherwood, to whom he entrusted the manuscript. Forster, who died in 1970, wanted “Maurice” to be published after his passing. He didn’t believe it was possible for such a story to be released in his lifetime. And judging from the largely condescending reviews it received in 1972, it appeared he was right. “Maurice” is not only an “openly gay novel,” it’s an attack on the class from which he came and the literary culture that thought it knew him.

“Maurice” was greeted with snarky condescension — except in gay political circles where it was heartily embraced.

Merchant-Ivory’s decision to create the film was a daring one. With James Wilby, Hugh Grant and Rupert Graves at the apex of their beauty, Merchant-Ivory were not pressed to be “sensational” in the mise en scene. “Maurice” isn’t “The Boys in the Band.” But it isn’t “Sunday Bloody Sunday” (its nearest gay “relative”) either. It’s a film that’s both of Edwardian England and 1987 at the same time.

Forster was exceedingly scrupulous in making his titular hero an intelligent, but in no way “remarkable” man. Obviously well educated, Maurice (James Wilby) is not an intellectual or an aesthete “of the Oscar Wilde sort,” as he calls himself after first fully recognizing his gay desires. That isn’t clear to him right away. His love for fellow student Clive Durham (Hugh Grant) remains platonic, while edging close to the fully physical. A scene in which his professor (Barry Forster) advises a student reading a classic text aloud to skip a passage concerning “the unspeakable vices of the Greeks,” sets up a confrontation with a fellow student (Mark Tandy) who has clearly given into them. When this same student is arrested for coming on to a Royal Guardsman (notorious in their history as hustlers for the rich and famous) and goes to prison for it much like Oscar Wilde, the example of his ruined life is all Clive needs to call off his affair with Maurice.

“What is to become of me,” Maurice cries when Clive tells him it’s all over (a deeply moving moment beautifully played by Wilby).

He gets his answer when Alec Scudder (Rupert Graves), the under-games-keeper at Clive’s estate, climbs through his bedroom window at night and makes love to him. For a gay man of that era, fearful of his own desires as much as the wrath of society, this is the ultimate sexual fantasy. Yet as “fantastic” as it might seem, Forster takes it quite seriously. Because of his love for Scudder, Maurice will not simply “get over” his tortured semi-affair with Clive, he will turn his back on British society and, as Mark Twain would say “head off for the territory.” This is what Edward Carpenter did.

But it isn’t the route Forster — the man himself — took. For rather than head to the country, Forster found his own “Scudder” in town — a policeman named Bob Buckingham. That Buckingham was married didn’t complicate matters, as his wife was apparently amenable to her husband having his novelist as a love “on the down low.”

It might have been interesting (though obviously less romantic) had Forster contrived an ending to Maurice directly in line with his own life. But in the course of writing the book he made a number of significant alterations that explain why he didn’t do so.

Originally, Forster penned an epilogue depicting a meeting between Maurice and his sister Kitty some years later. Alec and Maurice have by now become woodcutters. He doesn’t explain it fully to her, but it becomes clear to Kitty why her brother disappeared. This portion of the novel would have underlined the extreme dislike that Kitty feels for her brother. The epilogue ends with Maurice and Alec in each other’s arms at the end of the day, discussing seeing Kitty and resolving that they must move on to avoid detection. Happily, for gay audiences, Foster eschewed this melodrama.

A typical critics reaction was Roger Ebert’s review of the film; he declares the ending impossible to believe since Maurice and Alec are from different classes and, he surmised, in that era would never have spoken much less formed a life together.

Clearly, critics like Ebert failed to understand Forster’s point, which is echoed not only in his own life but that of other gay artists of his era.

W. Somerset Maugham’s lovers, Gerald Haxton and Alan Searle, were both from the lower middle classes. Likewise Terence Rattigan’s lover, Michael Franklin.

Rattigan recognized the genius of a lesser class, playwright Joe Orton, whose “Entertaining Mr. Sloane” he praised. Orton, precisely the sort of lower class “lout” that attracted Rattigan sexually, was thoroughly committed to writing “well-made plays” in the Rattigan manner — though sexually radical in content. Rattigan said his ideal audience was a figure he called “Aunt Edna,” and in tribute Orton created “Mrs. Edna Welthorpe,” a comic persona he used to write cheeky letters to people regarding their “goods and services.” Had Orton not been murdered by his mentally unbalanced lover, Kenneth Halliwell, he might well have followed Rattigan’s example and ventured into the cinema.

A lot has happened since 1987. Not just that Ismail Merchant — Jim Ivory’s partner in life and art — has died (as a result of an ulcer operation) but legions of gay men died in an AIDS epidemic that, when “Maurice” was first released, was just getting its full head of deadly steam. People like Maurice and Scudder died by the score — Denholm Elliot, who played the doctor that advises Maurice, among them.

Yet the love of Maurice and Scudder persists among gay men even today. We are, all of us, either waiting by a bedroom window or climbing up a ladder into one, in a world that Forster could never have dreamed possible.

Merchant-Ivory’s film reminds us that though he’s been dead for 46 years, E.M. Forster is still very much alive in us all.

Cohen Media Group has re-mastered 30 films by the legendary Merchant Ivory Productions, including Maurice, which is set for release in select theaters this month.