It is difficult to know whether the elegiac mood I felt while reading The Shepherd's Crown was due to the book itself or to the fact that the fifth Tiffany Aching novel (and forty-first Discworld novel) was in fact the late Sir Terry Pratchett's final work.
The Shepherd's Crown focuses on the young witch Tiffany Aching as she comes fully to find her place both in the non-hierarchy of the witches' world, in the land of her birth (the Chalk), and in her own life. She finds herself pulled between two steadings, the districts for which, as a witch, she is responsible for doing "what needs to be done" — whether visiting the old and sick, birthing babies, or protecting the inhabitants from supernatural invasion. And, as the book begins, a supernatural invasion does in fact loom: Nightshade, Queen of the Faeries (whom a nine-year-old Tiffany defeated in the first book in the series) finds that the boundaries between her world and Tiffany's are weak, and she is planning large-scale revenge. Discworld faeries have much more kinship to the Celtic sidhe than to the cute winged creatures of most children's books or than to Tolkien's aristocratic elves: they are (literally) glamorous, pitiless creatures who take delight in mayhem ranging from spoiling beer and stealing sheep to kidnap, torture, and murder.
Much of The Shepherd's Crown centers on Tiffany and her allies (the other witches, the six-inch-tall Nac Mac Feegle) preparing for and ultimately dealing with the elvish incursion.
The characters were always the strong suit of Pratchett's novels — that and the wild humor. Throughout, we meet up of some of the most memorable characters from the previous forty Discworld novels, particularly the women — Eskarina Smith, Agnes Nitt, Queen Magrat, Nanny Ogg, and of course the indomitable Granny Weatherwax.
In fact, Granny Weatherwax has what I found to be the most memorable scene in the book, a somber, quiet passage that set the tone for the whole novel.
At the same time, we meet a few new characters, most notably a young pacifist named Geoffrey Swivel and his goat Mephistopheles. As Eskarina Smith wished to become the first female wizard in Equal Rites (one of the earliest Discworld books), so Geoffrey decides to become the first male witch, and turns to Tiffany for tutelage.
Most of Pratchett's writing was notable for its biting satire and wild humor. While there is definitely humor in The Shepherd's Crown, it feels very subdued. Nanny Ogg and the Nac Mac Feegle crack jokes, but there's definitely a whistling-in-the-graveyard feel to them. Even the author's notoriously random footnotes feel more wistful than riotously funny.
There's one other thing that sets The Shepherd's Crown apart from Pratchett's other books. Riotous could well describe the plotting in the earlier volumes in the Discworld series; some of them felt like improvised affairs, held together by brilliantly funny prose, wonderful characters, and fascinating explorations of social themes. In the last decade-plus of his life, the author seemed to be wrestling the chaos of his plots into submission. The plotting in the first four Tiffany Aching books, for example, is tight and well-paced while continuing to be surprising — a masterful balance of Aristotle's formula that the perfect plot lead to an ending that is both inevitable but unexpected.
In his final novel, there's much less of the unexpected. Events unroll in a satisfying manner, but rarely do they surprise.
This leaves me to wonder whether Pratchett's late-found discipline with regard to narrative form might have come as a result of his struggles with early-onset Alzheimer's disease — that as his memory became less reliable, he was forced to tame his myriad-minded genius for invention. This, however, is probably a pointless speculation, and finally irrelevant.
Pratchett was a brilliant, insightful satirist who happened to turn to fantasy as his medium, but whose novels and stories constantly pushed the reader to re-examine assumptions and prejudices. As such, The Shepherd's Crown may not have been his crowning achievement, but it is a fitting and satisfying cap on an magnificent career.