Joseph Lateiner (1853, Iaşi - 1935) was a playwright in the early years of Yiddish theater, first in Bucharest, Romania and later in New York City, where he was a co-founder in 1903 with Sophia Karp of the Grand Theater, New York's first purpose-built Yiddish language theater building.
Lateiner got his start writing for theater in Iaşi, Romania around the start of 1878, when Israel Grodner, having left Abraham Goldfaden's Bucharest company, needed a playwright. He added some topical material to a comic German story Nathan Schlemiehl, and came up with a play Die Tzwei Schmil Schmelkes (The Two Schmil Schmelkes). He translated and "Yiddishized" plays from Romanian and German; his more than 80 plays included Mishke and Moshke: Europeans in America (or The Greenhorns), Satan in the Garden of Eden," and "The Jewish Heart.[1]
By showing that Goldfaden was not the only person who could write a successful play in Yiddish, he opened the floodgates for other Yiddish playwrights.