'Goodbye to All That' is a phrase famously used in literature to express a sense of disillusionment and farewell, particularly to the ideals and experiences of youth. It resonates deeply within the context of World War I literature, where writers grappled with the stark realities of war, the loss of innocence, and the profound changes in societal values that emerged in its wake. The term captures a bittersweet acknowledgment of leaving behind former beliefs and aspirations as a result of the harrowing experiences faced during the war.