Poul Anderson shows up on Appendix N several times; I’ve already dealt with his Three Hearts and Three Lions, and late last year I pounced on The Broken Sword. Between the two, and despite being the earlier novel, I think The Broken Sword is the stronger work—though I see in it fewer direct influences on fantasy gaming.
The novel is the tale of two changeling children—Skafloc, a human babe stolen away to Faerie by the elves, and Valgard, the fate-damned and insane changeling left in the human’s stead, who eventually joins up with the elves’ troll opponents. These two characters grow, but ruin and tragedy follow in their wake, such as when Skafloc falls for a pretty maid who (unbeknownst to them) is his mortal sister; there’s plenty of derring-do and adventure, but at its core The Broken Sword is a tragedy in the Shakespearean sense: they all die at the end. Despite that grim nature, reflecting its Norse inspiration, it’s a pretty solid novel that any gamer with serious literary ambition should read, if you don’t mind a rather stark novel. For more plot detail, see my review here.
In terms of fantasy, this was released mere months before Tolkien’s Lord of the Rings reached the United States; there’s several similarities in that both use Norse myth as a starting point, but while Tolkien wanted to establish his own mythos, Anderson clung very close to the pattern of old sagas, leaving us with a kind of modernized myth. It’s worth noting that Tolkien wasn’t the dominant force in fantasy until the late-’60s/early-’70s when Ace printed the first (unauthorized) paperback edition, and the LotR edition wars between Ace and Ballantine launched its popularity not just among SF readers, but with Vietnam War vets and other mainstream readers. That was, conveniently enough, around the time Anderson revised his novel.
See, the 1970s revision for Ballantine’s Adult Fantasy line was heavily amended. In the process Anderson removed the baroque prose that made it so vivid and unique, yet reflected a clear connection to the Norse sagas of old. (The novel’s set on the British isles, and has a strong “tales of Faerie” flavor, and at times it feels much like the pre-Tolkien fantasies written in England.) For a modern reader, the 1970s version may be more approachable, though the 1954 version carries the heritage of real-world myth in its very bones, and I’m hard-pressed to recommend the revised version.
So, what in The Broken Sword was influential to D&D? Well… not that much, to be honest. I’m having to stretch to find some of these connections, as there’s nothing as blatant as the paladin, troll, and alignment found in Three Hearts and Three Lions. Most of the themes The Broken Sword introduced to fantasy roleplaying games are elements in third-party materials or homebrew campaigns—tropes that players and gamemasters recognize and use, but not themes that are all that common in D&D fiction. (I’m talking big-F fiction; not just the novels, but the world/setting details, the adventure modules, and other game aids.)
Warring Religions, Divine Machinations, and Gods Walking as Men
Come to think of it, most original D&D didn’t really go much into monotheism or religious tension/conflict, which are core themes of the novel. And while there were Gods (see Deities and Demigods), who quite often walked the world as mortals do, I recall a lot of the immortals as player-characters who’ve just grown in level and power (cf. the Immortals box set). Of course, the Forgotten Realms setting has a lot of gods walking around as mortals–-time of troubles say what?–-and it’s become a common theme in more recent editions. As have religious wars, or at least conflicts/friction between deities. Few deal with a deity’s power waxing and waning depending on the strength of their follower-base–-something I’ve seen in D&D-influenced fiction, but not in D&D or its RPG siblings. Nor do I recall any struggle between pantheism and monotheism—D&D is safely set in a pantheon mindset, kept far away from potentially offending religious groups while retaining that “ye olde” Medieval fantasy flavor.
At any rate, The Broken Sword depicts the war between Faerie and Trollheim, but this is a very small piece of a larger conflict within the Old Gods pantheon—the Norse gods and the Jotuns use Faerie and Trollheim as pawns in their giant chessboard. Rather than fight it out directly, they manipulate and expend Faerie and Trollheim in their own proxy war. Now and then they walk about, having to do some hands-on manipulation of those pawns—Odin make some appearances, as do the Celtic pantheon who, bereft of followers, are in their twilight years. Beyond that, there’s a sharp division between the “old gods” and the burgeoning growth of Christianity which is just expanding in the British isles: Christian mortals are safe from pagan influences and superstitions such as the Evil Eye, as this new monotheism drives the warring pagans back into the darkness. Even as the Aesir plot towards their own ends—literal ends against the Jotuns at Ragnarök—their religion is being superseded by the new monotheism.
Mythic Realms of Shadow
D&D has had a long tradition of other realms and realities, mythical worlds all around us that we simply cannot see, a theme which has grown with each edition. 3rd and 4th Editions were rife with overlapping realities—other worlds and planes, Pathfinder’s First World and 4e’s Shadowfell, all kinds of realms which overlay and overlap our mortal plane. The Broken Sword takes it one step further: there is a divide between worlds, and mortals cannot see or tell the presence of a supernatural creature; they can feel their presence—sense and hear their bloody battles and the troll occupation of England. Most mortals are protected either by their worship of the old gods, others by their Christian beliefs. Those who have blasphemed are offered no protection; one scene has Valgard reach Trollheim and then give up his viking crew to the trolls, and unable to see their aggressors the mortal men are slaughtered.
Again, not a direct trope in D&D—the game would be a lot different if the supernatural critters you’re supposed to hit with swords are things you can’t see. But it’s a close proxy for D&D’s planar cosmology, bringing to mind 4e’s Feywild and Pathfinder’s First World, both inspired in part by the realm of Faerie. Thematically, there’s also are some similarities between The Broken Sword‘s overlapping realities and, say, the old-school “points of light”-type setting that puts human civilization—well, all Lawful mortal civilizations—in a sea of untamed wilderness, isolated and juxtaposed by the Weird that surrounds them: savage and deadly creatures, ruins of long-lost civilizations, forgotten artifacts of great power.
The Magic Blade
The broken sword in the title is Skafloc’s birth-gift from the Norse Aesir, a magic blade that influenced Michael Moorcock to design his own. This sword is magic, and all who wield it are destined for great victory in battle—but the blade also brings ill fortune and much suffering to its wielder. This sword of fate is a good inspiration for some of D&D’s magical weapons—including the cursed ones, for a cursed sword it is. D&D has loved offering risk-reward magic items that gave characters impressive powers but at a cost, and such is the case here: a sword of wrath and fury, blessed for victory and damned to bring ill fortune to its wielder.
Elves and Trolls
Anderson’s elves are not Tolkien’s elves, and thus have few similarities to what D&D elves are like: they tend to be well-armed and well-armored, and are quite capable of magic, a hybrid warrior-mage that BD&D and the Rules Cyclopedia made into the Elf class. They’re also more Chaotic than Good, not understanding things like morals or love, and instead doing things because they want to do them.
Trolls are much like the troll Anderson introduced in Three Hearts and Three Lions, and are big, brutish, and vulnerable to fire. Anderson describes them thus, with a recurring skull theme:
…arms like tree boughs that hung to their knees…Their skin was green and cold and slippery…few of them had hair…eyes set far into bone-ridged sockets, were like skulls.
As per tradition, both are vulnerable to cold iron—while many creatures are vulnerable to cold iron weapons in recent D&D editions, including fey and various types of evil outsiders (demons, devils, etc.), neither elves nor trolls usually have that specific weakness. (Part of this is due to separating elves from fey, and in part, I assume, for some degree of balance as trolls already have a weakness to fire.)