This is a special collection of the Dorot Jewish Division of New York Public Library consisting of "Placards from the two leading centers of Yiddish theater in their respective heydays: New York, 1890s-1910s (64 images), and Buenos Aires, 1930s-1940s (28 images)".
From the project website:
"The Dorot Jewish Division's Yiddish Theater Collection contains the materials assembled by many of the founders of the art form, from the notoriously flamboyant matinee idol and impresario Boris Thomashefsky to the comparatively sublime Bertha Kalich and the impossibly dignified Morris Morrison, as well as their young Harvard-educated aficionado, the bibliographer Edward Coleman. It is the principal repository for the unpublished manuscripts of these early Yiddish plays, for whose contents there is generally no other surviving evidence. The Library is home as well to an unparalleled array of publicity materials, often verbose and unfailingly hyperbolic, proclaiming the early productions of the New York Yiddish stage, as well as a representative sample of the more restrained announcements that heralded Yiddish theater productions in Buenos Aires in its belated years of glory during the 1930s and 1940s. Many of the New York placards were collected and presented to the Library by Yiddish magazine publisher Chonon Yankov Minikes, whose 1897 anthology Di Idishe Bihne [The Jewish Stage] was the first book published in America to explore and celebrate the Yiddish theater."