Which major battle does J.R.R. Tolkien’s The Children of Húrin center on?

J.R.R. Tolkien’s The Children of Húrin centers on the Battle of Unnumbered Tears, also called Nirnaeth Arnoediad.

The battle is a major conflict of the First Age, fought when the forces of the Noldorin Elves and their allies attempt to defeat Morgoth in Beleriand. The alliance initially appears promising, but treachery and the strength of Morgoth’s armies turn the battle into a devastating defeat.

Húrin fights in the battle and is captured after resisting Morgoth’s forces. His captivity and Morgoth’s curse drive much of the tragedy that follows in the lives of Húrin’s children, Túrin and Nienor. This battle is different from the later Battle of Five Armies, which occurs in The Hobbit.