As a bookseller, the question I get most is, 'Which one is first?' The simplest answer I give: 'Look for the one where the main character is named Thomas of Hookton and he's young. That's the first.' Usually that's 'Harlequin' or 'The Archer's Tale'. Then just read the next two with the same guy. The others are fantastic, but they're like bonus tracks.
The fandom for this series is pretty dedicated over on historical fiction forums. I'd hop on a site like Reddit's r/historicalfiction or the historical fiction section on Goodreads and just ask. Someone there will not only give you the list but probably argue about the merits of reading the prequel first or last. Those communities are amazing for niche series details that broader sites sometimes miss. You might even get the author to chime in if you're lucky; some of them frequent those spaces to chat with readers.
I've seen lists that include 'The Fort' in the 'Master of War' sequence, which is utterly wrong. That's a different war, different century. Stick to the Hundred Years' War books. The core quartet is your answer. Any list longer than four books for Thomas's story is incorporating standalones or unrelated series.
It's not even a close comparison for me. Publication order has a weird hiccup where you go from a tense, present-day siege in book one to a centuries-old political drama in book two. It's jarring and made me put the series down for a year. A friend convinced me to try the fan order, and it was night and day.
The story flows like a single, epic tale instead of a disjointed collection. The character motivations in the 'later' books make so much more sense when you have the 'prequel' context earlier. I'd only recommend publication order to scholars studying the author's development, not to readers looking for a great story.
Interesting. I always thought the Sharpe books were the beginning of everything. I didn't even know about this 'Master of War' collection until now. Shows what I know!