Carl Seiler and Madelyn (née Hughes) Seiler gave birth to Mark Edwin Seiler on May 2, 1948, in Glen Cove, New York. He was brought up in Sands Point, Long Island, where he went to Buckley Day School, Choate Rosemary Lobby, and Paul D. Schreiber Secondary School, prior to moving on from Tulane College with a BS in Financial matters.
In the wake of graduating, Seiler regarded himself as in Hollywood and went to work for RKO Pictures, a restoration of the celebrated Hollywood studio brand and the film and video auxiliary of RKO General Inc., which itself was a unit of Gencorp Inc.
Having invested some energy as leader of RKO Film Gathering, a 37-year-old Seiler was named RKO Pictures president in July 1985, supplanting C. Robert Manby. Seiler persuaded Jerry Offsay, an attorney, to leave his position as a partner at Loeb & Loeb in Los Angeles to join RKO and take over the film group. On faith, he gave me the chance to switch from law to creativity. I want to believe that he generally knew how thankful I was for changing my life [by] taking me to RKO," Offsay said in a proclamation. Offsay would later become leader of programming for Kickoff Organizations and presently runs his own organization, Parkchester Pictures.
Seiler was notable for his ability spotting capacities, both inventive and leader ability. After observing the young actor's work in theater, Seiler, then a young RKO executive, played a significant role in the casting of Denzel Washington for the George Segal dramedy Carbon Copy. The 1981 film would turn into Washington's element debut. In one more prominent model, Seiler, alongside Offsay, by and by picked the youthful Wear Cheadle, Dylan McDermott, Courtney B. Vance and Steven Weber for the cast of Cheeseburger Slope.