For most purposes, two of Eddison's works matter, "The Worm Ouroboros", published in 1926 (I've seen 1922 listed), and the Zimiamvian trilogy, written over the two decades that followed.
"The Worm Ouroboros" (***+) is an epic fantasy told for its own sake. Eddison was drunk on the English language, and produced a florid, elaborate, somewhat archaic prose, with many long passages and (he hated to see one of his sentences come to an end) relatively few periods. But it works. At first the style is in the way, then it stops irritating, and at some point you realize that it's drawn you in. Eddison was also drunk on fantasy, in the tradition of bygone centuries, with larger-than-life heroic characters climbing the unclimbable, slaying the unslayable, and generally being more concerned with glory than with whether or not next year's crops were planted. Again, it works.
It works despite the first twenty pages or so, which set a standard for inauspicious beginnings. How inauspiciously can a fantasy begin? Well, to start with, the action takes place on the planet Mercury, for no apparent reason. Worse, the author heavy-handedly introduces the story as one which a character is dreaming. And, for no apparent reason, the warring nations of the story are named "Demons", "Witches", "Goblins", Pixies", etc., though they have no relationship to the supernatural beings who usually bear those names. (The Demons actually do have horns, but...) I make special note of the flaws in the opening so that if you pick the book up, you'll know to grit your teeth and keep reading: After the first couple of chapters the dreamer is forgotten, the pretense that the story takes place on Mercury is ignored, and the names...well...you really do get used to them.
(Introducing a story as a dream is an old convention, and one that used to be in more common use. It dates back to a time when a dream was thought of as something that one could be granted, rather than purely as the product of the unconscious mind. As such, calling a story a dream could reinforce the suspension of disbelief, rather than undercut it.)
Somewhere between the second and third chapter you can start forgetting the opening artificialities and be drawn into the tale: The long-standing rivalry between Witchland and Demonland, the insulting Witch embassy, the failed attempt to settle the enmity, the war, the quest, the heroism of Lord Juss, the treachery of Lord Gro (who is the most engaging character in the story, despite his little flaws), the conjurations of Gorice XII...
Do I seem to be dealing out left-handed compliments? The book has it's flaws -- the more from the perspective of the modern reader, who is used to more rounded characters and less ornate language -- but it is still a stylistic triumph. There are echoes of Shakespeare and echoes of Homer (not to mention some out-and-out purloining), but mostly it is E.R. Eddison having a wonderful time and inviting the reader to join him. Some readers won't like it and some readers will love it. There are enough of the latter that, if you think you might be one of them, the book is worth trying.
The Zimiamvian Trilogy is Eddison's lesser work. Try it if you read and enjoyed "The Worm Ouroboros". It takes place in a land that is less fantastic and more medievalish, but is still a land of heroes and armies and plots and intrigues. The language is more modern and less convoluted, but still busier than we've come to expect in our novels. The main hero of the trilogy is Lessingham -- who appears briefly in "The Worm Ouroboros" as the dreamer. (As in Worm, female characters, even the strong ones, tend to have peripheral or supporting roles.) The trilogy was published as three separate books, and has recently been reissued in one volume. One of the quirks of the trilogy is that the books appear (and should be read) in reverse chronological order.
"Mistress of Mistresses" (***) is the first and best of the three -- the story of the intrigues and conflicts which follows the death of King Mezentius of Zimiamvia. The chief villain of the piece is Horius Parry, the Vicar of Rerek. And what truly complicates matters is that Lessingham, although a good and true hero, is also Parry's active and sworn supporter. (Good news: The prose, although not as magical as it is in Worm, is easier to read. Bad news: There's still one of Those first chapters to get through, in this case the 'Overture'.)
"A Fish Dinner in Memison" (**) is self-indulgent. Zimiamvia is under the firm rule of King Mezentius, and the characters who war and intrigue in "Mistress of Mistresses" are more circumspect. ('Circumspect' is anappropriate word. Eddison's characters are often noble and glorious, but a certain amorality accompanies those characteristics.) There is some fighting, but there is more flirting. There is, eventually, the dinner party of the title. Meanwhile, and in parallel, we have the story of Lessingham's courtship, on our own world. (An odd symmetry is at work. In "Mistress of Mistresses", Zimiamvia is revealed as a world created by the Goddess for Lessingham's benefit. In "A Fish Dinner in Memison", Earth is revealed as a world created at the behest of Her Zimiamvian avatar.)
Eddison died before finishing "The Mezentian Gate" (**?), but we have Eddison's outline of the missing pieces, so the whole tale of Mezentius's life holds together tolerably well.
I'm ambivalent about the Zimiamvian trilogy. The characters are admirable, but rarely likable; the writing is masterful, but self-indulgent. I'd guess that if you enjoy "The Worm Ouroboros", you'll find the trilogy to be weaker, but still worth reading. If you don't enjoy "The Worm Ouroboros", don't try the trilogy.
Dani Zweig firstname.lastname@example.org