Books VIII, IX, and X of Le Morte D’Arthur form mostly a single narrative, which sounds way, way better than it is, because what it is is a meandering narrative that has no point and very little dramatic arc. So strap yourself in, because this is an awful ride. Much like Arthur’s obligatory origin story in Book I, it begins well before Tristram’s birth.
Once upon a time in Cornwall, there was this guy Meliodas, the King of Liones, which is a region in (or near) Cornwall. His wife, Queen Elizabeth, was the sister of King Mark of Cornwall (last seen making an inexplicable cameo way back in Book II). Arthur was Meliodas’s direct supervisor: Arthur, Malory reminds us, had a lot of subsidiary kings. There were two in Wales, two in the North of England, two in Cornwall (Mark and Meliodas), two or maybe three in Ireland (Malory isn’t sure), plus the Kings of France and Brittany and Benwick. And there were also a bunch of kings in between France and Rome from Book V when Arthur conquered Europe, Malory reminds us. This is a huge continuity error since during Books IV, V, and VII references were made to Sir Tristram as though he and the lovely Isoud had been already a going thing. And yet we’re now led to believe that when Elizabeth and Meliodas (spoiler alert, these would be Tristram’s parents) got together, Arthur already had the fealty of a big pile of kings on the continent. It’s like Malory isn’t even trying, here.
Meliodas and Elizabeth were married, and happily they were just nuts for one another, which you don’t see much in Le Morte D’Arthur. Elizabeth got pregnant lickety-split! Eight and a half months later, Meliodas went out hunting, like you do when your wife could go into labor at any moment. Some witch saw him, and of course she lusted after him. She used magic to trick him into chasing an illusory hart through the wilderness. Meliodas chased this imaginary hart right into a ruined manor house out in the middle of nowhere. Shockingly enough, the manor house turned out to be an enchanted prison, where the witch locked him up and tried to seduce him.
Maybe this was a particular thing for Malory, a knight getting imprisoned by a witch who wanted to seduce him. Morgan le Fay did it to Launcelot in Book VI, and variations come up a few more times. Regardless, the king pined only for his wife; the witch was just out of luck. No seductions happened, which is also what happened when Morgan le Fay tried to sleep with Launcelot under similar circumstances.
Meanwhile, at the same time, Queen Elizabeth noticed her husband was missing. Somewhat bizarrely considering she was a woman in a story written by Malory, she didn’t just sit around and wait for a guy to solve her problems! Instead she went out searching for Meliodas. She was hugely pregnant, so she brought along exactly one servant, her midwife, in case she had to give birth in the field.
Sadly though, the worst happened, or nearly the worst: Elizabeth went into labor, way out in the middle of nowhere. She and the midwife cooperated to bring little Baby Tristram into the world, but the strain of it killed her. Death in childbirth was sadly common in the benighted past. Poor Elizabeth, out in the middle of the woods, lacked even the traditional boiling water and clean sheets.
As Elizabeth died, she delivered a monologue. “When you find Meliodas,” she told her midwife, “give him my love, and tell him I wished he was here for this, the birth of our son, and that I miss him and I’m sorry to have to leave him in the lurch like this. Tell him about how I went looking for him, so maybe he’ll know how much I loved him.
“Oh, my son.” Queen Elizabeth took little Baby Tristram in her arms. “I’m guessing you’ll grow up to be a mighty knight. You’ve already slain your first lady, and you don’t even know how your hands work yet! But before I go, little murderer, I name you. I name you Tristram.”
Malory helpfully explains Tristram means sorrowful birth. My wife, whose undergraduate degree was in medieval French romances, has told me this is not unambiguously true. I don’t know who to believe! But I can assure you that Elizabeth’s quip about Tristram already slaying his first damosel is totally canonical, in case you wondered.
Once Elizabeth had died, a convenient posse of Meliodas’s knights and barons appeared; they’d been out looking for Meliodas. Or Elizabeth. Somebody, anyway. When they saw Elizabeth dead and Tristram born, they got the smart idea of killing the baby, calling Meliodas dead, and fighting over his throne.
But Elizabeth’s legacy was so great, and her death scene so touching, that it inspired her midwife to extemporaneously give a lengthy speech about how great Elizabeth had been, how precious Baby Tristram was, and how the barons should have been ashamed of themselves for even considering infanticide.
Chastened, the barons recanted their murderous intent. They escorted the midwife and Baby Tristram and Elizabeth’s body home.
Meliodas met them there! It turns out that as soon as Elizabeth had died, Merlin’d appeared and rescued Meliodas from his witch-prison! Malory does not dwell on it. That’s what happens. Deal with it. I guess this is set before Book IV.
When Meliodas learned Elizabeth had died, the sorrow that the king made for his queen that might no tongue tell, Meliodas was pretty upset, and he stayed pretty upset for seven years.