I had never heard of him before reading this thread, but with a web search I found this:
"With the appearance in 1938 of his first book, In Dreams Begin Responsibilities, twenty-four-year-old Delmore Schwartz was immediately recognized as a genuinely innovative force in American letters, drawing praise from T. S. Eliot, Ezra Pound, Allen Tate, John Crowe Ransom, Wallace Stevens, and William Carlos Williams; for Tate, it was "the only genuine innovation we've had since Eliot and Pound." A decade later his book of short stories, The World Is A Wedding, was characterized by many critics as the definitive portrait of their generation. Yet Schwartz's early promise was followed by a tragic decline and finally death in a midtown Manhattan hotel at the age of fifty-two."
Also his books, including In Dreams Begin Responsibilities are listed at Amazon.com.