Howel, King of Brittany, turned out to have a problem. This one earl, Grip, had been making trouble for him: refusing taxes, assaulting officers, laying siege to Howel’s house, that kind of thing. As you may recall from Book V, Brittany had long suffered a severe heroic knight shortage: when a rampaging giant abducted and eventually murdered Howel’s wife, all Howel could do was sit back and hope for the best. Arthur and Kay eventually slew the giant, but that was years before. When Tristram came, Howel’s son, Sir Kehydius, had grown up to be a halfway decent knight, and the closest thing to hero Brittany had. Kehydius tried to joust with Earl Grip, but it didn’t go very well for him; I said halfway decent, not actually decent.
“I don’t know what I’m going to do, here,” Howel said afterwards, sitting one evening with a few guests and friends. “My son’s not up to the task of defeating Grip. My retainers and I are all much too old.”
Gouvernail, who had been hanging out with Howel a fair bit during Tristram’s convalescence, had an idea. “My lord Sir Tristram is incredibly valiant, up there in the highest echelons of knightliness alongside Sir Launcelot and his kind. Ask him to fight this Grip for you.”
“A compelling notion!” cried Howel. “All of Brittany is agog with tales of Tristram’s valor. I don’t know why I didn’t think of it myself, actually.”
Howel talked to Tristram, and Tristram agreed to joust Grip, and he did, and he won, and then there was a party. It’s not worth spending any more time than that on it.
After the celebratory party Howel announced his retirement: he was too old to defend Brittany against giants and troublemakers like Grip. Brittany needed a strong young king, and since his own son Kehydius was laughably inadequate, Howel offered his kingdom to Tristram.
“Sounds good,” said Tristram. “Free kingdom; what’s to turn down?”
Howel had just one condition. “You need to marry my daughter, Isoud the White.”
“Can’t think of a reason not to,” said Tristram.
Tristram and Isoud the White were married the very next day! But on their wedding night, a revelation struck Tristram.
“Crap, I just remembered,” he told his bride as they lay together. “I can’t sleep with you, Isoud. I’m in love with Isoud. I should have mentioned it sooner. I just forgot. It’s been an eventful few days.”
“Wait, what?” asked Isoud the White Hand.
Tristram explained. Isoud the White Hand wasn’t exactly thrilled with the news, but she accepted the situation. So Tristram and Isoud didn’t have sex! Malory was very clear on this. Second base only, he says. You think I’m kidding? Other cheer made he none but with clipping and kissing. Boom! Direct quote.
Everything was okay for Tristram for a few months. But then one of Sir Kehydius’s friends named Sir Suppinabiles visited Camelot. While there, he told everyone all about the new King of Brittany, Tristram de Lions, and how great he was. Defeating Earl Grip, marrying Isoud the White, and so forth.
When Launcelot heard about the wedding he did a spit-take. “What? Sir Tristram married Isoud the White? But he’s in love with Isoud! You don’t get to marry some random wench when you’re in love with a king’s wife! That’s ridiculous! How dare he? How dare he?”
“Launcelot, my friend. You seem to be taking this news awfully personally,” said King Arthur. “Is there something I should know?”
“No,” said Launcelot and Guenever in unison.
“Well, that’s good.” Arthur leaned back in his chair.
“It just burns my biscuits, is all,” Launcelot continued. “I always liked Tristram, even though we’ve met only briefly. But if he’s going to go around marrying the wrong Isoud like that, he and I aren’t friends. You tell him I said that! Next time I see him, we joust!”
Sir Suppinabiles returned to Brittany. “I’m back from Camelot,” he announced.
“Did they mention me at all?” Tristram asked.
“Cool! What’d they say what’d they say?”
“So, you know Sir Launcelot…”
“My good friend whom I’ve never met, and my knightly role model!”
“Yeah. He said he hates you and he’s going to kill you, because you’ve been unfaithful to the lovely Isoud.”
“Really? He said that?” Tristram was crestfallen. “Stupid wife. I should never have married Isoud. Darn it. Darn it all.” And of course he became super morose.
The lovely Isoud and Guenever were penpals, did you know that? After Palomides set it up, they exchanged letters all the time. Guenever wrote to the lovely Isoud, describing the account she heard of Tristram’s wedding. The lovely Isoud was heartbroken to hear about this betrayal by her man (“her man” !== her husband), and told Guenever so. Guenever wrote her back an unexpectedly ominous note:
“Oh honey, oh sweetie, oh, listen. Men are idiots. Men are fools, you remember that. Tristram can hardly be expected to remember you exist while you’re not standing in front of him. Very few knights have mastered object permanence. Thats why ladies like you, and me, and Morgan, and so on, that’s why we use sorcery to manipulate men. Eventually you’ll get your Tristram back, never fear. His marriage to Isoud the White will totes go south, I promise. Kisses, Guenever.”