Arguably one of the eeriest places in Middle Earth is the Dead Marshes, which Gollum leads Frodo and Sam through on the way to Mordor. It is a quiet and demoralizing land, without any birds or living things, so they try to give Gollum some Lembas bread, which chokes him. As they peer into the murky water, they see ashen faces peering back at them, and Gollum explains that there was a deadly battle fought there long ago which resulted in the loss of many lives. So what was this battle, and who are the people that fought in it?
The fight, known as the ‘Battle of Dagorlad’ took place in the Second Age of Middle Earth, when the evil Lord Sauron first rose to power. A host of elves and men known as the Last Alliance marched from their kingdoms all around the Misty Mountains to meet him in battle and prevent him from taking over Middle Earth. Two elven armies, led by Malgalad and Gil-galad, were joined by warriors of Men led by Anarion and Elendil, the two kings of Gondor upon whom one of the Argonath are based. But the elven armies were not united, and half of them charged against the enemy before the command was given, which resulted in them being slaughtered on the spot. The battle is said to have raged for months, in which the alliance painstakingly pushed the enemy back through the black gates and to the fields which eventually became known as the dead marshes, due to the thousands of bodies who came to find their final resting place there.
A great many of Sauron’s forces were displaced, forcing him to withdraw and regroup his orcs ready for another onslaught. A further seven years passed with the Alliance trying to maintain the vantage that they had gained, and Sauron re-weaponizing his army ready for the next stint of the fight. After the seven years, the Alliance had pushed back the foes so far that Sauron himself entered the battle, coming to the war zone in his physical form.
This is the scene from the prologue of the Fellowship of the Ring, in which Elrond of Rivendell is fighting, and Isildur cuts the One Ring from Sauron’s finger, shattering the blade Narsil which is later reforged to become Aragorn’s Sword. In the version in the books, Thranduil, who many viewers will recognize as Legolas' father from The Hobbit films, was also involved in the battle, and after losing his father Oropher, was forced to return to the woodland realm of Mirkwood, just north of Fangorn Forest.
The set for the Dead Marshes was built and filmed in the car park of the filming studios in New Zealand. The hills and mounds within the marshes were built using sandbags, which were then painted and covered in grass and moss. The set was then flooded with a mixture of water and colored paints to give the water its sort of greenish sickly color.
The dead bodies in the water were prosthetic dummies built by the amazing sculpting and costume teams of Weta Workshop, and then they were fully submerged to create the drowned effect. The background of the scene was filmed against a green screen and then digitally added later by Weta Digital, as well as the pervasive soundscape of battle-cries and swords clashing that gives the scene its ominous feeling. The little flames that can be seen were a combination of actual fire and digital enhancement. As for these strange lights throughout the dead marshes, there are many theories about what exactly they are.
Although the books are not explicit, they do describe them as ‘dimly shining smoke’ or ‘misty flames flickering slowly above unseen candles.’ Many Lord of the Rings fans believe the lights to be the shimmering souls of those unrestful dead who thrive below the waters, whereas others believe the lights to be a kind of Will O'the Wisp. The legend of these strange creatures comes from old English folk-tales and fairy stories, meant to act as a warning and a deterrent from wandering off the path on a dark night where one can easily get lost.
Stories have changed over time, but the original concept for these wisps was that they would lead foolish travelers into the marshes where they would drown, which fits with the concept of Lord of the Rings as Gollum, who used to be Smeagol says ‘Don’t follow the lights.’ However, the legends changed at some point to suggest that Wisps had become spirit guides who were trying to help lost travelers and lead them back to safety. It could be suggested then, that the lights of the Dead Marshes are Willows that have gathered around the dead trying to lead the souls there out of their dark trapped state, and into the proper resting places of their people, i.e. for the elves it is the Undying Lands, and for the men of Gondor it may be the burial mounds of their forebears.
There is a theme throughout the Lord of the Rings, this idea of people and their spirits being trapped until they have found peace or achieved their purpose. The same can be seen of Gandalf who is trapped on the tower of Orthanc, the Soldiers of the Dead who are trapped until they fulfill their oath to Aragorn, and the Ringwraiths, who are trapped in a realm somewhere between living and death. Many of the other creatures are able to find peace after the war of the ring is won, but it is never stated whether or not the souls of the Dead Marshes ever find their way out of their watery graves.