I am looking for detailed information on the evolution of European armor in the 14th century, specifically the transition from partial- to full-plate and the concurrent use and abandonment of shields. I am concerned primarily with armor used in actual warfare, NOT in tournaments or jousting.
I know some basics of this evolution, from the addition of small solid steel plates over a coat of mail in the late 13th century through the basically complete full suits of plate armor by the end of the first quarter of the 15th century. What I am specifically interested in, if possible, is a detailed decade-by-decade coverage of the transitional period where the number and complexity of steel plates increased.
As a corollary to this, I am also interested in the evolution of shields alongside this transition in armor styles. In the early 14th century, if I understand correctly, the standard knightly shield was the "heater" shield, commonly seen in heraldic escutcheons. By the end of the century large heater shields had largely given way to smaller bucklers or targes, or had been abandoned completely as the protection from a full suit of plate made use of a shield rather redundant. Again, though I am aware of the beginning- and end-points of this transition I am particularly interested in understanding this change in the scale of decades rather than centuries.
There is a huge profusion of books listed on Amazon about medieval armor, but most seem to cover a far larger timespan than my specific interest in the 14th century. I am also more interested in an academic-style work with detailed sources and terminology over a more "pop-history" introduction-level coverage of the subject. Any suggestions on an appropriate work to acquire for such in-depth coverage would be greatly appreciated.
The best book on medieval armour is Alan Williams monolithic Knight and the Blast Furnace. While the main thrust of Williams work is on the metallurgy and craftsmanship of medieval armour (most plate) he does also cover the development of plate armour. That said, the book is expensive, long, and excruciatingly detailed so it might not be the best diving in point.
The more classical book for the history of medieval armour is Claude Blair's European Armour c.1066-c.1700. Blair's work is really the foundation for the modern academic study of the development of medieval armour and it has held up pretty well, even if its age is beginning to show now.
It has been a few years since I really dove into the study of plate armour, though, so I'm a bit rusty on it. /u/WARitter may have some other ideas of good books/articles.
So, u/valkine is absolutely right about both Williams and Blair. They are both wonderful and really really informative. I recommend them to anyone studying plate armour.
However, neither is quite what you requested. Unfortunately, there's isn't a single-volume, focused history of the development of plate armour through the 14th century out there. There are general studies (and in addition to Blair I'd add Edge and Paddock's Arms and Armour of the Medieval Knight, which is at many libraries and has a lot of illustrations). And there's also focused studies of individual pieces and collections - in particular, Bengt Thordeman's Armour from the Battle of Wisby, which covers the armours recovered from mass graves dating from that 1361 battle. But these are all either more general or more focused than what you're asking for.
Honestly, reading a general history and then digging into surviving effigies yourself may be the best bet. Given the lack of complete surviving armours from before 1400, effigies are really essential. Just the other day I found this website which combines effigies and brasses from multiple sources. I wouldn't use it as a sole source, but it could be useful to add more data points. Just be aware that the date on a funerary monument is generally the death date of the person depicted...not necessarily the date when it was carved, which could be earlier or later.
Back on topic, if I had to recommend one book it would be Blair. He arranges his topic more chronologically and less topically within the century than Edge and Paddock do. If you read him you'll get at least a good 50 page summary of the topic.
A Knight and His Armor by Ewart Oakeshott is a small (and inexpensive) book, but it covers the transition from mail armor to plate harness to include a detailed description of most of the pieces in a full harness and how they evolved.
Oakeshott is most famous for his descriptions of medieval swords, but he also wrote on many other topics including armor and shields. The companion book to A Knight and His Armor, titled A Knight and His Weapons, touches on sword and shield a bit, but not as thoroughly as you might want. It might still be worth picking up if you enjoy his other work.