The Katha-Upanishad is probably the most widely known of all the Upanishads. It was early translated into Persian and through this rendering first made its way into Europe. Later Raja Ram Mohun Roy brought out an English version. It has since appeared in various languages; and English, German and French writers are all agreed in pronouncing it one of the most perfect expressions of the religion and philosophy of the Vedas. Sir Edwin Arnold popularized it by his metrical rendering under the name of "The Secret of Death," and Ralph Waldo Emerson gives its story in brief at the close of his essay on "Immortality."
There is no consensus of opinion regarding the place of this Upanishad in Vedic literature. Some authorities declare it to belong to the Yajur-Veda, others to the Sama-Veda, while a large number put it down as a part of the Atharva-Veda. The story is first suggested in the Rig-Veda; it is told more definitely in the Yajur-Veda; and in the Katha-Upanishad it appears fully elaborated and interwoven with the loftiest Vedic teaching. There is nothing however, to indicate the special place of this final version, nor has any meaning been found for the name Katha.
The text presents a dialogue between an aspiring disciple, Nachiketas, and the Ruler of Death regarding the great Hereafter.