Three major research books on Tolkien that have been published recently (one each from this year and the two preceding) have recently crossed my desk and my eyetracks. All are products of deep and meticulous research, for which the authors deserve all honor. The conclusions they reach, however, may be another thing.
John M. Bowers, Tolkien's Lost Chaucer (Oxford UP, 2019)
Tolkien spent years working on the language notes and glossary for an edition of Chaucer selections that never got finished or published, partly (though only partly) because Tolkien was a perfectionist who wrote about four times as much as OUP, the publisher, wanted for a book aimed at undergraduates. This matter was an obscure footnote in Tolkien studies until Bowers revealed the sheer extent of the project by going through all the surviving correspondence to write a history of the 30 years this dragged on, plus uncovering a large box of surviving galleys and drafts in the OUP basement and quoting from them liberally.
That's the first half of this book, and it's brilliant and valuable. For the second half, Bowers has gone through The Lord of the Rings (he has little interest in the rest of Tolkien's creative writing) looking for things that remind him of something in Chaucer, and blithely assuming that Tolkien copied Chaucer like an amanuensis. It doesn't work that way. The connections he finds range from the trivial to the nonsensical, and his assurance that nobody would have known how important Chaucer was to Tolkien without unearthing the scale of this project is absurd. It's always been well-known that Tolkien was a Chaucer expert, and there's plenty of articles on Chaucer's influence on Tolkien, not all of which find their way into Bowers' extensive bibliography. What I conspicuously miss is anything connecting Tolkien's scholarly method in his Chaucer philology with the nature of the detail he put into creating his fiction: this could have been a rich source of study, but it wasn't.
Holly Ordway, Tolkien's Modern Reading: Middle-earth Beyond the Middle Ages (Word on Fire, 2021)
Tolkien has a reputation of being only interested in medieval literature. Ordway is out to prove that he was also well-read in modern literature and had a lot to say about it. This book goes systematically through Tolkien's known encounters with post-1850 English-language literature (because there have to be some limits), discussing its character and what Tolkien would have gotten out of it, on which topic Ordway is a solid analyst.
This, too, is brilliant and valuable, and the extent of Ordway's research is impressive. The thoughtfulness with which she proceeds makes her book much more valuable, for its area of coverage, than Oronzo Cilli's mechanically-compiled and rather sloppy Tolkien's Library. The problem - the first problem with this book - is that Ordway writes as if she's made a great discovery, but most of what she writes about is well-known in Tolkien scholarship. What she has written is a great work of synthesis, and the revelation is of how much there is put here in one place for the first time. The second problem is her attribution of Tolkien's standard reputation to Humphrey Carpenter's biography. This leads to an epic bout of Carpenter-bashing, far beyond his deserts. The third problem is Ordway's tendency distinctly to underplay the extent to which Tolkien disliked a lot of this modern literature that he read. She doesn't omit this, but there's a notable lack of emphasis. The standard reputation is actually less that Tolkien didn't read anything after Chaucer but that he didn't like anything after Chaucer. There turns out to be a lot more truth in this than one would think from the pitch Ordway is trying to sell.
Ordway has no religious agenda, but the publisher is a Catholic ministry, and if you order the book directly from them you'll start getting in your e-mail daily homilies from some bishop until you send an unsubscribe message at least twice.
John Garth, The Worlds of J.R.R. Tolkien: The Places that Inspired Middle-earth (Princeton UP, 2020)
Previous books on the inspirations of Tolkien's geography have followed the John Bowers method, actually well-known to all cheap-rent source-hunters, of touring around England looking for places that remind the tourist of something in Tolkien and blithely assuming that Tolkien just copied them. Garth doesn't do that. Despite its sub-title, this is not a guide to places that inspired Tolkien, and it can't even be conveniently used for that purpose. It's actually a guide to the inside of Tolkien's mind, in its geographic, landscape, and geological facets. The coverage is thematic - there are chapters on mountains, waterscapes, forests, archaeology, towers (yes, towers), and battlefields - and the focus is always on Tolkien's invented places and what he was trying to accomplish by creating them. Real places (with generous photographs) are brought in only insofar as there's a documented connection in Tolkien's mind; or, if there's widespread speculation by reputable scholars, Garth labels it as such. Garth even goes to the trouble of debunking several popular but fanciful theories of Tolkien's geographical inspirations. There is no guesswork or blithe assumption in this book. As with Ordway, little of what Garth describes is new to scholarship. This is a well-researched work of synthesis, reinforced by Garth's sharp and clear understanding of how Tolkien's mind worked. That overall viewpoint, together with the systematic coverage, is what Garth really brings to the table.
All three of these books are greatly useful for the worthwhile things they accomplish, but this one is the best, and one of the most valuable books out there for understanding Tolkien.