In 1892 he emigrated to the United States, settling in Philadelphia, Pennsylvania; only then did he develop an interest in Yiddish literature and theater (Schulman & Denman 2007).
In the U.S. he first worked menial jobs in Philadelphia, as well as in rural Pennsylvania, and New Jersey, before moving to New York City (Sandrow 1986, p. 172).
Kobrin's first play, Mine (Minna), was rewritten and adapted by Jacob Gordin for a production in 1899, with the original text appearing in print later the same year (Sandrow 1986, p. 169-170; Schulman & Denman 2007).
Liptzin singles out Kobrin's tragedy Yankel Boyle (1908, based on his own 1898 story) as the "apex" of his work, and describes its title character as "a kindhearted but dull-witted Jewish youth … embroiled in a complex moral and emotional dilemma to which he could find no solution short of suicide" (Liptzin 1972, p. 81).
Among the authors whose work he translated were Guy de Maupassant, Émile Zola, Maxim Gorky, Leo Tolstoy, Fyodor Dostoevsky, and Anton Chekhov.