I’ve just reread your Grail trilogy yet again. Particularly interesting for me because, since I first read them, I’ve lived in Flanders, driven sheep (with a bilingual border collie) the other side of the hill from Azincourt, own a small place in Bretagne, have wandered the Midi-Pyrenees from Narbonne, to  Albi & across to the Atlantic coast right through the Gascony of Heretic. I’ve lived in houses which, although built more recently, wouldn’t differ markedly from the buildings of the time & passed every day a slighted castle no different from Astarac.
My question returns to one you had in 2010. How Guy Vexille would have pronounced his own name.  An English speaker, of course would have it as Veksill, but seeing it only a line away from Sir Guillaume d’Evecque it’s obvious the doubled Ls would be pronounced in the French manner & the elision of the X sound closer to Z. Vekzeey rather than your Vexee because the French do not slur the Y sound as much as us Brits. But was Vexille a French speaker? His family were the victims of the Albigensian Crusade. Presumably Cathars. As you so rightly indicate in the book, Occitan was the language of the south, not French. I’ve heard some Occitan & quite a lot of Catalan which is similar. The X sound is more CH. In fact it’s common for the two spellings to be used interchangeably xica for chica in text speak. Chilches & Xilches for signs to the same town just south of Castellon. So we could have Vecheey. But what about that V? The English V of my mother’s Vera is not the V of my ex’s Véronique. The hard V is from northern, Germanic languages. The French V is much less distinct. But Catalan doesn’t have a V sound at all. Spanish, Catalan, French, Occitan are all decendents from Latin & the Latin V was a softer W sound. Catalan & Spanish have mutated that to a B sound. So Vexille, himself, may have said his own name much closer to Becheey.

Currently I seem to have ended up in Andalucia. Carthage for us history enthusiasts. Our local, Arab built, castle at Fuengirola has a tale to tell. A small English fleet sailed up the coast from Gib & landed cannon & troops to storm it. Unfortunately they were thoroughly routed by the Polish garrison (my Polish g/f loves this) who sallied, captured the cannon & turned them on the ships. (she’s been known to replay this bit with crockery if I stay too late at the bar).  And a small slice of myth from much further north & further back in time. Do you know the Aveyron valley in the Tarn et Garonne? The town of St Antoine Noble Val crouches beside the river, overshadowed by the looming, perpendicular limestone cliffs of the gorge & fell to an English siege. Local legend has it the English used to throw captives off the top & if you stand on the bluff looking down at the town, it’s easy to see how a well aimed Frenchman could be interred in his own graveyard without recourse to a shovel.

Vexille again…..Just been reading through the other reader comments regarding your villain & it bothers me whether he is truly the villain of the trilogy.
The Hookton character is hardly a saint. The English campaign from Britanny up to Crécy would be judged now as terrorism. It was intended to be. Essentially economic warfare. Thomas does his fair share of sacking & pillaging & is later in Gascony embarking on more of the same. He’s a mercenary, primarily in it for the spoils Vexille, however, is a very different character. There’s not much known now about Catharism. Like always, history gets written by the victors & Cathar writings were mostly destroyed. Cathars rejected the hierarchies of the Roman church in favour of a simpler faith based  more closely on the scriptures. How much of their practices resembled the  lurid claims of the Church is largely a mystery. It’s possible it’s the seeds of Catherism that, much later, flowered into the Protestantism of Northern Europe. Now, again, Vexille’s a man of his time. When the ends very much justified the means. But it’s d’Evecque ravages Hookton. Vexille’s killing of Father Ralph & later Abbot Planchard both can be seen as retribution for the desertion of the Cathar cause when Montségur fell. And Vexille’s antipathy towards his cousin Thomas similarly. It fits very much with the mentality of the times, grudges being passed down through families. So,let’s look at Vexille in a fresh light. He’s dedicated his life to recovery of the Grail & using it to cleans & renew European Christianity. He does what he considers necessary believing he’s about God’s work.  Essentially, he’s one of the few moral characters in the books.
Pete Lunt