Karl Koehler was born in Manhattan and grew up in the Bronx.
He attended Holy Cross College and, after medical school, completed psychiatric training in Cornell and Heidelberg. Later, he was appointed professor of Social Psychiatry in Bonn.
His first novel, GUMPELMANN, was published in German in Berlin in 2004.
A corrected English version, PSYCHIATRISTS UNHINGED, appeared in the USA in 2013.
A shorter text, PORNOGRAPHY AND PSYCHIATRY, offers a literary analysis of this novel.
His second novel, BERNSTEIN'S BERLIN, deals with the difficulties of Jewish assimilation in Germany, especially during the tumultuous years of the Weimar Republic.
His third novel RATZINGER'S ISLAND, takes the reader on a tour of madness inside a man's head, as he struggles with his religious and theological obsessions.
His fourth novel, THE JESUITS AND THE HOUNDS OF HEAVEN, inspired by Francis Thompson's poem, focusses on the existential bewilderment of four boys from the Bronx at a Catholic college, somewhere in New England, during the early Fifties.
His fifth novel, BACK FROM THE BRONX, focusses on two marginalized men, trying to come to grips with growing old and the loss of their youthful dreams
Some of his free time is spent playing songs from the Great American Songbook on the piano, listening to country blues, and actively supporting his local baseball team, the Bonn Capitals.
He lives with his wife in the Cologne area.