“Just a note to tell you hams that we had a little disturbance out here,” Paul Spangler, a Navy doctor, penned in a letter to his friends, “and it was sumpin’.” The “little disturbance” was Japan’s attack on Pearl Harbor, and Spangler, who was stationed in Hawaii, would spend most of the next three days performing surgeries. Spangler’s message was one of more than fifteen thousand collected as part of the Legacy Project, an initiative by the historian and editor Andrew Carroll, in order to make public the previously unpublished letters of American soldiers.

In December, 1999, The New Yorker ran a selection of the letters, each written during the twentieth century’s major American conflicts. The thirteen messages encompass a startling range of tones and perspectives, dated slang and mixed emotions. In France, a fighter in the First World War pronounces himself “busy with Uncle Sam’s affairs,” then describes waiting for hours in a shell hole, where he stood in waist-deep water “like ice, and there were five dead Huns floating around in it, too.” Decades on, a released prisoner of war in Korea writes to the mother of a fallen comrade, recounting the final time he saw her son and sending along her son’s Bible as a “dear remembrance.” Still later, a soldier in Vietnam condemns the conflict and describes the week that followed his first ambush, a period that involved smoking opium and “a little pot,” which he experienced as almost “one continuous high.”

Sorrowful and angry, playful and courageous, the letters make for remarkable reading. “People should understand what war means,” another soldier writes shortly after Japan’s surrender. “Maybe then they won’t start another.”