In the autumn of 1908, Kilmer was employed teaching Latin at Morristown High School in Morristown, New Jersey. At this time, he began to submit essays to "Red Cross Notes" (including his first published piece, an essay on the "Psychology of Advertising") and his early poems to literary periodicals. Kilmer also wrote book reviews for "The Literary Digest", "Town & Country", "The Nation", and "The New York Times". By June 1909, Kilmer had abandoned any aspirations to continue teaching and relocated to New York City, where he focused solely on developing a career as a writer.