Paths of the Dead – Dwimorberg Pass
The Paths of the Dead was an underground passage also known as the Dwimorberg Pass. The Dark Door marked the entrance of the Paths of the Dead through the Dimholt forest of black trees.
The people of Rohan knew the Paths of the Dead were cursed as no one survived nor returned after taking the passage.
The Paths of the Dead was taken by the ghosts and wraths of the Oathbreakers(in the movie known as the Army of the Dead) that were haunted by the curse of Isildur.
King of the Dead, Oathbreakers – Army of the Dead, Dead Men of Dunharrow
Who were these ghosts and wraiths of the Paths of the Dead? These men were natives of the White Mountains that lived before Gondor and Rohan was founded.
When Gondor was founded, the Men of the Mountains that were led by their king that would later become the King of the Dead swore loyalty to Isildur.
When Isildur called upon the Men of the Mountains and their king to join the Last Alliance of Elves and Men to defeat Sauron, the Men of the Mountains hid deep into the Dwimorberg Pass and broke their allegiance and oath to serve Isildur.
Isildur brought upon a great curse on the Men of the Mountains for their betrayal and the Men of the Mountains became wraiths and ghosts that couldn’t rest in peace.
Led by the King of the Dead, the Men of the Mountains became the ghosts of the Dwimorberg Pass.
In the movie they were referred as the Army of the Dead. Also called the Dead Men of Dunharrow, these wraiths believed that the heir of Isildur was cut off and gave up on hopes of resting in peace until Aragorn.
Aragorn’s entrance to the Paths of the Dead
Aragorn along with Gimli, Legolas(and the Grey Company and Elladan, Elrohir) entered the Dark Door and through the Paths of the Dead.
In the movie, the King of the Dead appears in front of Aragorn mocking his company so that no one could exit the Paths of the Dead alive.
The King of the Dead draws his sword while Aragorn defends himself with the blade Anduril, forged from the shards of Narsil.
Aragorn’s sword blocks the sword of the King of the Dead that surprised him because no ordinary living being could block physical contact of ghosts.
Oathbreaker’s pledge of loyalty to Aragorn, the heir of the king of Gondor
Aragorn then reveals that he was the bloodline of Isildur, the heir of Isildur that could release the Oathbreakers from their curse.
In the movie, King of the Dead denied Aragorn at first as no one on Middle Earth knew that the bloodline of Isildur survived since the fall of Arnor and its descending countries. In the novel, the Oathbreakers guide Aragorn through.
In the movie after Gimli, Legolas and Aragorn barely manages to escape the avalanche of the skulls and escape the Paths of the Dead. Aragorn then witnesses the corsairs of Umbar pillaging and destroying the southern lands of Gondor.
While Aragorn was in despair, the King of the Dead exits the Paths of the Dead and pledges loyalty to Aragorn, Isildur’s heir.
Relief of Southern Gondor
The lords of Southern Gondor couldn’t send many reinforcements to Minas Tirith because the corsairs and pirates of Umbar flooded the lands. The corsairs of Umbar pillaged and ravaged the lands of Southern Gondor as they’ve sailed north to join Gothmog’s forces at the Pelennor Fields.
Aragorn along with the Oathbreakers, Gimli, Legolas, the Grey Company with Elrohir, Elladan and Halbarad wiped out the corsairs that invaded Southern Gondor.
They were able to clear out the pirates of corsairs all the way through Pelargir.
Reinforcements to Minas Tirith
In the novel, instead of the Oathbreakers the Army of the Dead, 3,000 reinforcements from Southern Gondor head to Minas Tirith as reinforcements.
In the movie, it would have made the movie much complicated so the Oathbreakers boarded the ships of the corsairs of Umbar and headed to Minas Tirith with Aragorn.
Release of the Oathbreakers and Fulfillment of Isildur’s Oath – Novel
In the novel, after Pelargir was liberated from the Umbar corsairs, Aragorn released the Oath breakers and declared that they’ve fulfilled Isidlur’s oath.
After the help of the Oath breakers, the lords of Southern Gondor could now mobilize their troops and send them to Minas Tirith. On the ships of the Umbar corsairs, Aragorn heads to Minas Tirith to save Gondor.