Published in 1954, the same year as Tolkien's The Fellowship of the Ring saw publication, it is tempting to compare Anderson's novel to the Ring Trilogy. Both works are influenced by Norse mythology, shades of the Poetic Edda are obvious in The Broken Sword; however, while Tolkien took Norse Mythology and molded it to fit his vision of Middleearth, Poul Anderson took a more literal approach with The Broken Sword. Perhaps a weakness of Sword is that it reads as if written by a writer trying too hard to emulate a story form he obviously holds in high regard.
There were moments while reading passages of the novel that I found myself doing an inward eye roll. That aside, it is a delightful read and is without a doubt a true classic of Sword and Sorcery literature. I am careful to not say Fantasy in the generic sense. While it is a novel that would fall under the large banner of Fantasy in the genre sense, I would consider it more in the vein of Sword and Sorcery. Not quite in the vein of the works of Robert E. Howard or Fritz Lieber, but more similar to that of Lord Dunsany or even William Morris.
I only make this distinction as Poul Anderson does not attempt to create his own world here; while Tolkien took his Norse influences and created his own world clearly outside of the boundaries of reality, Anderson's tale takes place in a fictionalized England during the period of Viking incursions. Populace superstitions of the realm of Faerie are real and can be sensed from time to time upon the margins of society. Anderson's Faerie realm is perhaps a dimension which shares our own. As are the realm of Jottenheim and the Norse Gods.
Anderson's elves are not Tolkien's elves. They are, in Dungeons & Dragons terminology, Chaotic. The affairs of mankind not only do not interest them, they are perhaps beneath them. Here is perhaps the first influence which can be seen upon the development of Dungeons & Dragons. Comparing this novel to Anderson's novel Three Hearts and Three Lions, in which a definite alignment system is developed by Anderson, the rudimentary beginnings of on alignment system may be viewed in The Broken Sword, although it is not clearly as drawn out. Perhaps also an early influence upon what would become the standard Troll in D&D is here as well: