This article examines the intersection of the Yiddish modernist Yankev Glatshteyn’s poetics of old age with the cultural politics of language. Specifically, the article draws on Robert Pogue Harrison’s concept of “heterochronicity”—the ability to embody many ages at once—to investigate how a young Yiddish poet textualized old age and age ambiguity in his early work. To do so, the article first investigates the cultural assumptions concerning age in European Yiddish writing circulating toward the end of the nineteenth century and the beginning of the twentieth. It then turns to Glatshteyn’s early work, “Mayne lider” (My Poems), in which the heterochronic management of old age functions as a rejoinder to Glatshteyn’s American Yiddish literary predecessors and as a model of his modernist poetics. Finally, the article turns its attention to Glatshteyn’s 1925 poem “Tsu mayn tsveyhundertyorikn geburtstog” (“On the Occasion of My Two-Hundredth Birthday”), analyzing the text as a tendentious reading of T. S. Eliot and the hierarchy of Yiddish-English difference. To grow old in Yiddish was not simply a biological experience for Glatshteyn. Rather, it was an aesthetic commitment—a mode of writing energized by heterochronic entanglements, intertextual confrontation, and the intersecting age-driven assumptions of Yiddish literature and Anglo-American modernism.