Théoden

The King of Rohan, roused from Wormtongue's spell to lead the Rohirrim to Gondor.

Théoden is the King of Rohan in The Lord of the Rings, Lord of the Mark, who is first met weak with age and the whispers of his adviser Gríma Wormtongue and ends as the leader of the Rohirrim at the Battle of the Pelennor Fields.

Quick Facts

Series: Middle-earth
Also known as: Lord of the Mark, King of Rohan
Race: Men of Rohan

Facts from the source article.

Background

When Gandalf, Aragorn, Legolas and Gimli come before him in The Two Towers, he is largely controlled by Wormtongue, secretly Saruman's agent, while orcs and Dunlendings trouble Rohan; Unfinished Tales suggests Gríma's subtle poisons hastened his decline. Once Gandalf exposes Wormtongue he comes to his senses, restores his nephew, takes up his sword Herugrim and leads the Riders of Rohan to victory at Helm's Deep, then watches Gandalf break Saruman's staff at Orthanc.

In The Return of the King he leads the Rohirrim to the aid of Gondor at the Battle of the Pelennor Fields. There he routs the Harad cavalry, personally killing their chieftain. He challenges the Witch-king of Angmar, leader of the Nazgûl, but is mortally wounded when his own horse Snowmane falls upon him. His niece Éowyn and the hobbit Merry Brandybuck, who had ridden to war in secret, destroy the Witch-king. His body lies in Minas Tirith until he is buried in Rohan, and his nephew Éomer succeeds him as the last of the Second Line descended from Eorl the Young.

The name is the Old English þēoden, meaning king or prince. Scholars compare him to Theodoric, King of the Visigoths, who also died in battle, and contrast his openness with the harshness of Denethor.