In the following article we will examine Germanic dwarf lore and how these beings might fit into Fyrnsidu cosmology.
In Anglo-Saxon Sources
While dweorg/dweorh appears a number of times in Old English glossaries, the most significant example appears in the Lacnunga manuscript metrical charm, Wið Dweorh. The charm, which translates as Against a Dwarf is a ward against illnesses caused by dwarfs, which Edward Pettit equates with fever.
The metrical charm is translated into modern English as follows.
“Take seven little wafers, such as those used in worship, and write these names on each wafer: Maximianus, Malchus, Iohannes, Martimianus, Dionisius, Constantinus, Serafion. Then sing the charm that is given, first in the left ear, then in the right ear, then over the top of the head. And then let a virgin go to him and hang it on his neck. And do this for three days. He will soon be better.
A spider-thing came on the scene
with his cloak in his hand; claiming you for his horse,
he put his cord on your neck. Then they began to cast off from land;
as soon as they left the land they nonetheless began to cool.
The beast’s sister came on the scene;
she stopped it, and swore these oaths:
that this should never hurt the sick one,
nor any who tried to take this charm,
nor any who should speak this charm.
In this example, the dweorg is clearly a being of malefic intent who is capable of causing sickness and bodily harm to mortals. While Pettit’s assertion is that Dweorg is analogous with fever, Matthew C. G. Lewis argues it may constitute an entity which causes sleep paralysis, akin to the Germanic Mara (OE Mære). Lewis speculates that the reference to a ‘spider-thing’ alludes to a binding feeling common to episodes of sleep paralysis. As this is an article dealing largely with the metaphysical aspects of the dwarf as it pertains to Fyrnsidu, we will not traverse further down this rabbit hole, suffice to say it elucidates possible characteristics and capabilities of dweorgas and like-entities as purveyors of physical oppression.
In Norse Sources
In Vǫluspá, dwarfs are described as being the product of the bones of Blain and the blood of Brimir, both of which are considered bynames of the primordial giant, Ymir. In the Prose Edda, the connection to Ymir is more concrete, as the dwarfs are purported to be maggot-like creatures who grew in the flesh of the giant. Over 100 names are given for dwarfs in both Eddas, with four in particular being given a cosmological role as beings who hold up the sky and are named for the four cardinal directions. 
Depictions of dwarfs in Norse lore are often complex and confusing, with significant overlap occurring between dwarfs, elves, giants and trolls. Scholars have noted the similarities between dwarfs and Svartálfar (dark elves), as both are listed as residing in Svartálfaheimr, suggesting a coupling of sorts.
This similarity is further established between elves and dwarfs by their shared propensity to cause ‘shot’, a type of malign, metaphysical pain. The term ylfa gescot (elf-shot) appears in Wið Færstice, an Anglo-Saxon metrical charm designed to ward against a ‘sudden stitch.’ This use of ‘shot’ appears to have been a shared Germanic concept, based on its inclusion in later German, Danish and Norwegian texts. Alvskot (elf-shot), trollskot (troll-shot) and dvergskot (dwarf-shot) all appear in later Norwegian usage , effectively blurring the line between elf and dwarf and their perceived malefic abilities.
Norse dwarfs, like their elfish counterparts, were frequently associated with the dead and liminality. In Ynglinga Saga, dwarfs are guardians of a doorway through a mountain which leads to the realm of Oðinn, a gateway which Lotte Motz suggests is a doorway between worlds. Lecouteux corroborates this belief in dwarfs being related to the dead, suggesting that those who suffer a premature, violent or unusual death are likely to be transformed into revenants or dwarfs rather than elves.
“This last name refers to a very specific characteristic of dwarves: the sun blinds and petrifies them. Undoubtedly even more interesting are the names that clearly show that dwarves represent a mythical vision of the dead, or, at the very least, that they have a very close bond with the dead. Here are several of them: Dáinn (“Died”), Nár and Náinn (both meaning “Corpse”), Frosti (“Cold”), Funinn (“Decomposed”), Dvalinn (“Torpid”), Hornbori (“Pierced by a Horn”), Haugspori (“The One Who Enters the Burial Mound”) and Búinn (“Readyfor-Departure,” i.e., for burial). To this list we can also add Nýi (“Dark”) and Niði (“New Moon”), since this planetary body is that of the deceased, and Ái (“Ancestor”), which clearly indicates the transformation of the dead into dwarves. Furthermore, the natural habitat of the dwarves is the lithic realm, which is of course that of the deceased.” 
Continental and Later Medieval Sources
Nowhere was the image of the dwarf more diluted and confused than in continental Germanic folklore. It was there that the dwarf (OHG: twerg, twerc, MHG: twerc, zwerc) was used as a gloss for a number of supernatural beings. In the Middle High German glossaries, zwerc was used as an amalgam for wiht, schrat, pilwiz, pumilo, nanus/pygmaeus and pilosus. Due to the fact that zwerc and schrat were conflated and the word schrat itself subsumed incubus, succubus, silvanus/silenus, fanus/panes, larva, penates and satyrus, studying the unique features of the continental dwarf has become a laborious exercise.
The comparisons to schrat and pilwiz are of particular interest here, as both can serve to buttress lore regarding dwarfs. In the most ancient glosses, schrat is glossed as larva and monstrum, or “dead one” and “revenant” respectively and as Lares mali, “evil Lares.” These glosses are suggestive of a maleficent, or at least amoral genius loci, similar to the beings described in Wið Dweorh. They also corroborate Lecouteux’s claim that dwarfs were likely viewed as revenants who had died tragic or untimely deaths.
The comparison to pilwiz (MHG: Bilwiss , Bilwiz, MLG: Belewitte) also provides confirmation that dwarfs may have served as genii loci, or house spirits prior to their power being dimished by Christian writers. In his lyrical poetry, Wolfram von Eschenbach refers to the Wilwis as an elf-like being able to shoot magic arrows called Bilwizschuß, “Bilwiz-shot” which can cause paralysis in humans. Grimm also provides the term pilbisbawm, or “Pilbis-tree”, a tree which is said to house an elfish genius loci.
Like the dwarf, pilwiz was a term which held many meanings, depending on the time period and geographic location, though, As Lecouteux says of genii loci in Demons and Spirits of the Land, “their shape, names and appearances were protean, but their role, duties, and localization remained unchanged.”
Dwarfs in a Fyrnsidu Context
Now that we have explored pertinent Anglo-Saxon, Norse and continental dwarf lore, we are able to assemble a more complete image of dweorgas[*] and how they might be approached by practitioners of Fyrnsidu.
As we saw in all three sections, dweorgas can be dangerous entities, possessing the ability to cause illness and paralysis by way of magic, if slighted. Dweorgas are also likely those who have suffered a premature or violent death, which may explain their latent erratic and malefic behaviour. They are seemingly able to oppress their victims during sleep, exerting their powers in the form of nightmares and sleep paralysis.
As genii loci (tutelary spirits), dweorgas are connected to specific geographic locations and homes. Though propitiatory offerings can and should be made, entering into a reciprocal cycle of do ut des would be both dangerous and ill-advised. As the dead are liminal beings, offerings might be placed in a nearby body of water or doorway in placation.
Dweorgas are also chthonic/infernal beings akin to the Dii Manes of the Roman religion, so gestures of appeasement during especially liminal periods of the year (Gēola, Winterfylleþ) are advisable to halt their encroachment.
 Edward Pettit, Anglo-Saxon Remedies, Charms, and Prayers from British Library MS Harley 585: The Lacnunga : Introduction, Apr 2001
Karl Young, https://www.thing.net/~grist/ld/young/ky-chrm.htm
 Matthew C. G. Lewis, Dreaming of Dwarves: Nightmares and Shamanism in Anglo-Saxon Poetics and the Wið Dweorh Charm.
 Simek, Rudolf (2007) translated by Angela Hall. Dictionary of Northern Mythology(2007:67–68)
 Simek (2007:305), Orchard (1997:35), and Hafstein (2002:111)
 De Vries, Jan. Altgermanische Religionsgeschichte, I, pp.296-7
 Motz, Lotte (1983). The Wise One of the Mountain: Form, Function and Significance of the Subterranean Smith: A Study in Folklore. Göppinger Arbeiten zur Germanistik
 Lecouteux, Claude. Garden Dwarves and House Spirits
Lecouteux, Claude. Demons and Spirits of the Land: Ancestral Lore and Practices. (pp.55-6)
Lecouteux, Claude. The Tradition of Household Spirits: Ancestral Lore and Practices. (pp.111)
Grimm, Jacob. German Mythology 1st volume (2nd edition), Dieterichsche bookstore, Göttingen (1844), page 441- 446
[*]The plural form *dweorgas is used here, though there doesn’t seem to be an existing plural form. The ‘as’ ending seems likely when we compare other masculine nouns with similar endings.