It's derived from the Medieval gay lovers that I first read about in The Young Folks' Shelf of Books during my early childhood.
I heard about them again in college, when my French Literature class was assigned a modern version of the 12th century Chanson de Roland, the national epic of France.

During the siege of Viana, Emperor Charlemagne agreed to let the outcome rest on single combat between two champions. He sent his nephew, the bold, heavily-muscled Roland, the Prince Valiant of France. Count Gerard of Viana sent his grandson, the handsome, quick-witted Oliver (or Olivier). Their talents were complementary; they were perfectly matched.
As they fought, an angel appeared, separated them, and bade them become friends (the same thing happened to Simon and Milo a few generations later).
They spent the rest of their lives together, fighting side by side, and their love, with its divine mandate, was acclaimed in every corner of Charlemagne's Empire.
Then the Saracens began wending their way through Basque country, In 778, the approached the pass at Roncevaux, Spain, in the Pyrenees. If they entered France, they would take all of Europe. Charlemagne and his troops tried to stop them. In the heat of battle, Oliver was killed, and the distraught Roland cried:
So many days and years gone by
We lived together.
Since thou art dead, to live is pain.
Then he died as well.
Actually, the battle had nothing to do with the Moorish caliphate; Basque guerillas ambushed Charlemagne's troops, in retribution for his destructiion of their capital, to rob them. Roland really existed, the leader of the Franks' invasion of Brittany, but there's no historical evidence for the existence of Oliver. The Chanson de Roland created him to be Roland's true love.
I didn't bother to point out the homoromance to my French professor, who no doubt would have insisted that Roland, like Aschenbach in Death in Venice, wasn't Wearing a Sign. He was betrothed to Oliver's sister, after all, and in the Italian epic Orlando Furioso, he falls in love with a woman (and flies to the moon).
More after the break
The 1978 movie version of La Chanson de Roland gives Roland (Klaus Kinski, left) an overwhelming hetero-passion. Oliver (Pierre Clementi, below) looks on with an unacknowledged, unrequited love.
Robert Browning gets rid of Oliver altogether in his famous poem "Childe Roland to the Dark Tower Came" (1855), leaving only the nightmarish landscape and atmosphere of doom.
Oliver likewise missing from Stephen King's portrayal of Roland in The Dark Tower. The 2017 movie starred Idris Elba as the frequently-reincarnated gunslinger who roams the wasteland and mourns his dead girlfriend.
Why is the love of men so often relegated to tales told to children, presented as mythical, like dragons, elves, and magic swords?







