The Battle of Pelennor Fields is one of the most crucial fights for Middle Earth that ever takes place. It is the turning point of the War of the Ring, in which many beasts battle, many brave soldiers lose their lives, and many kings are made and broken. The two realms of the West, Gondor and Rohan, fight side by side to save all that they hold dear, offering up some of their most courageous warriors, including Eomer who will later rule Rohan as the nephew of King Theoden, and Faramir the noble son of Denethor, who will become the next Steward of Gondor.
But arguably one of the most important knights left out of the films is Dernhelm. This young soldier is a crucial piece in understanding how the Battle at Pelennor fields was won. He is one of the brave riders who flies into the fray alongside the other people on horseback from Rohan. They journey through the dark, across the edges of the land, as the orcs build trenches all around and prepare to seize the white city of Minas Tirith. At the last moment, when there seems no hope and that Gondor will fall, the Riders of Rohan charge the fields and come to the rescue of their falling brothers. Among them, right at the front on the left hand side of the king, is Dernhelm. And in front of him, on his dappled grey horse sits Merry the hobbit. In the movies, the audience sees Eomer insult the halfling, saying “I do not doubt the strength of his heart, only the reach of his arm.” No one will take Merry to the battle, for no one believes that he is capable of fighting for what is right.
But Dernhelm has also suffered similar injustice, for the warrior was also bidden to stay home, and to protect the women and children because he did not know the true perils of war, and would surely quail if he saw them. But when it comes to the crucial moment, and king Theoden is tossed from his horse by a Fell Beast, the winged servant of the Nazgul, Dernhelm steps in between them to protect the king.
The Witch King dismounts his foul steed and warns the warrior “Come not between the Nazgul and his prey! He will bear thee away to the houses of lamentation, beyond all darkness, where thy flesh shall be devoured and thy shriveled mind be left naked to the Lidless Eye.” Despite the threats, and the cruel fate that seemingly awaits him, Derhelm stands strong and resolved, not cowering in fear as Eomer had suggested. The Fell Beast tries to advance, and Dernhalm laughs "the clear voice was like the ring of steel."
Finally, Dernhelm yells “No living man am I, you look upon a woman! I am Eowyn, Eomund’s daughter." And so it is revealed in the films, with the famous “I am no man!” that Dernhelm is actually Eowyn in disguise. In order to ride alongside the men, and gain some glory in battle rather than being trapped in a cage as is her greatest fear, Eowyn had to disguise herself as a man during the four long nights it took to journey in the dark from Helm’s Deep to Minas Tirith.
Although the name Dernhelm is not included in the film, and the exchanges in which he tries to keep himself from being revealed to the others are also left out, the audience is at least left with the conept of Eowyn disguising herself. But in defeating the Witch King, with the help of Merry, these two undervalued characters, who were thought to be of no use in a great battle such as this, actually complete one of the most essential and important acts of the entire War of the Ring.
For the Witch King was Sauron’s Right-hand man, his next in command, and in removing him, they have now taken two of the major threats to Middle earth out of play (the other being Saruman during the battle of Isengard). Sadly the king still dies, but he dies in honour and valor, and paves the way for Eomer to rule going into the Fourth Age of the world, alongside Aragorn who takes the throne of Gondor.
And Eowyn, who has long been trapped and suffocated by the closing walls all around her, is finally able to find joy within herself, after proving herself worthy in everyones eyes, including all those who once doubted her. After the Houses of Healing, she goes on to find love with Faramir of Gondor, and they have a son, who will later become captain of one of the finest and bravest armies that Gondor has ever known.