Etymologically speaking, the word devilry is a mixed word.
devil is ‘Anglo-Saxon’, in the sense that it exists in Old English (déofol) (though that comes via Latin from Greek).
-ry is an Old French suffix, a variant of -ery, ultimately itself a compound of Latin suffixes -ariu- and -ia.
-ry in Tolkien
Although it was not originally a native suffix, Tolkien seems to have quite liked -ry. Here are some examples of it:
hobbitry (Merry now had enough sturdy hobbitry to deal with the ruffians, LR vi. viii)
errantry (But her brothers, Elladan and Elrohir, were out upon errantry, LR ii. i; also the famous poem Errantry, LR ii. i; used in the first Earendel poem)
wizardry (six occurrences: e.g. You are mighty in wizardry, Gandalf the White! LR iii. viii)
ancientry (‘I would have her loved for her memory, her ancientry, her beauty, and her present wisdom’ LR iv. v, Faramir to Frodo; ‘This is a thing of worth beyond your reckoning. For its ancientry alone. It has no power, save the esteem in which those hold it who love my house. It will not help you, but if ever you are in need, my kin will ransom it...’ App. A. I. (iii), Arvedui to the Lossoth.)
ancientry (OED sense 1) is ‘The quality or estate of being ancient or very old; ancientness, antiquity...’
The frequency of devilry
Its highest frequency, in 1898: 0.000024%
after which it has declined; in 1941, when Tolkien was writing LR to: 0.000010%
and in 2000 to: 0.000004%
LR is around half a million words long and devilry occurs 12 times: 0.0024%.
The main meanings of devilry in OED2:
†1. A demon; a demoniacal possession. (Cf. French diablerie.) Obs. c1380 WYCLIF
2. Magical operation performed by the supposed help of Satan; dealing with the Devil; diabolical art. c1425
3. Works or operation of the devil. 1533
4. a. Devilish action or conduct; extreme wickedness, cruelty, or perversity; wicked mischief. 1637
devilry in LR
There are four instances where we need only assume OED’s sense 4a ‘extreme wickedness’, ‘wicked mischief’:
II. vii. (The Mirror of Galadriel) ‘There’s some devilry at work in the Shire.’
III. xi. (The Palantír) The devilry! What mischief has he done?
V. vi. (The Battle of the Pelennor Fields) What madness or devilry is this?
VI. i. (The Tower of Cirith Ungol) There was plainly some devilry going on.
However, I would argue that even here Tolkien intends a tinge of sense 2, ‘magical operation’, as in the remaining instances.
The other instances refer to phenomena regarded as magical in operation and malicious in motivation.
Four are associated with Saruman specifically:
III. vii. (Helm’s Deep) Devilry of Saruman! … They have lit the fire of Orthanc. [Aragorn]
III. vii. (Helm’s Deep) But the Orcs have brought a devilry from Orthanc. They have a blasting fire. [Aragorn]
III. viii. (The Road to Isengard) Saruman is brewing some devilry to greet us. [Éomer]
III. ix. (Flotsam and Jetsam) We feared that Saruman was brewing some new devilry for us. [Aragorn]
The other four are linked with Sauron (assuming, in the first example of all, that he ultimately controls the orcs of Moria):
II. v. (The Bridge of Khazad-dûm) ‘There is some new devilry here,’ he [Gandalf] said, ‘devised for our welcome, no doubt. But I know now where we are…’
IV. ii. (The Passage of the Marshes) Is it some devilry hatched in the Dark Land? [Sam, in regard to the dead in the marches]
V. iv. (The Siege of Gondor) How it [fire] was kindled or fed, by art or devilry, none could see.
VI. i. (The Tower of Cirith Ungol) It’s the gate. There’s some devilry there. [Sam, in regard to the Watchers]
As already indicated, the nearest sense is:
2. Magical operation performed by the supposed help of Satan; dealing with the Devil; diabolical art.
But Middle-earth is pre-Christian. There is no ‘devil’. However, there are instances of devil in LR:
V. v. (The Ride of the Rohirrim) ‘Anything that can keep so in this devil’s mirk,’ answered Elfhelm.
V. viii. (The Houses of Healing) ‘All I hope is that those murdering devils do not come to this House and trouble the sick.’ [Ioreth]
These are ‘casual’ uses by ‘untutored’ folk; but they surely cannot be OED’s devil n. sense 4a ‘a human being of diabolical character’; they have to be closer to sense 3 ‘a malignant being of angelic or superhuman nature and powers’.
The following words, not surprisingly, are not used in LR: diabolical, demonic, demon.
The distribution and effect of devilry
The word is most frequent in one book, Book III. It is generally weighted towards the end of the story, Books III, IV, V, and VI. It is clustered so that there are no completely isolated cases.
Its effect seems to be to introduce some of the power of the concept of devil into the representation of the antagonists despite the theological mismatch. The traditional attributes of the devil are malice towards all creatures, dishonesty and lying, mockery, malign powers, and temptation to do evil. All these, except the last, are evidently qualities that are attributed to the Enemy and his allies in LR.
This posting is a taster for my presentation at Liverpool Hope University’s Tolkien Symposium on Friday 11 November, entitled ‘Diction and Narrative in the Lord of the Rings’.