He failed an audition in 1877 for Abraham Goldfaden's nascent Yiddish theater company (which Mogulesko joined).
Within a year, he had joined the troupe of playwright Moses Halevy-Hurvitz, which toured through rural Romania and eventually to Chişinău, where his performance supposedly inspired David Kessler's interest in theater.
In 1882, at the Mariinsky Theater in Odesa, he scored a triumph in the first Yiddish-language production of Karl Gutzkow's Uriel Acosta.
[Adler, 1999, 269] With his wife Clara Schoengold, he followed much of the Yiddish theater community to London in the mid-1880s and thence to New York City.
Their son Joseph married Adler's daughter Frances in New York in 1911; both went on to be leading lights of the Yiddish stage.