What is the theme in The Waste Land by T. S. Eliot?

Disillusionment is the main theme. There are only two master themes in the poem, which in turn, generate many sub-themes. The first of these major themes is disillusionment, which Eliot indicates is the current state of affairs in modern society, especially the post—World War I Europe in which he lived. He illustrates this pervasive sense of disillusionment in several ways, the most notable of which are references to fertility rituals and joyless sex. First Eliot draws on the types of fertility legends discussed in Weston's and Frazer's books.