At which battle does Théoden die in J.R.R. Tolkien’s The Lord of the Rings?

Théoden dies during the Battle of the Pelennor Fields in J.R.R. Tolkien’s The Lord of the Rings.

The battle takes place before Minas Tirith during the War of the Ring. Théoden, king of Rohan, leads the Rohirrim in a sudden charge that arrives to aid Gondor against Sauron’s forces.

His horse is struck after the Witch-king of Angmar attacks. Théoden is fatally injured beneath the fallen horse, and his niece Éowyn confronts the Witch-king. With Merry’s help, she defeats him, fulfilling the prophecy that no living man would kill him.

The battle is sometimes confused with Helm’s Deep, another major conflict involving Rohan. Théoden survives Helm’s Deep and dies later, on the Pelennor before Minas Tirith.