By Stephen M. Silverman
Updated June 15, 1998 12:00 AM

Legendary actor Jason Robards Jr., 78, a back-to-back supporting actor Oscar winner (for “All the President’s Men” and “Julia”) and possibly the foremost interpreter of playwright Eugene O’Neill, died yesterday in a hospital near his home in Connecticut. He had been waging a long battle with cancer. His was a career that lasted half a century. Born in Chicago, Robards followed in the footsteps of his actor father, Jason Robards Sr. His Oscars were for playing real people. In “President’s Men,” he was Washington Post editor Ben Bradlee; in “Julia,” novelist Dashiell Hammett. He was also was nominated for his portrayal of eccentric billionaire Howard Hughes in 1980’s “Melvin and Howard.” Last year he received a Kennedy Center Honor and played Tom Cruise’s dying father in “Magnolia.” In his personal life, “I married everyone I ever went out with,” he once said. Of his four wives, Robards’s most famous was his third, actress Lauren Bacall (they have a son, actor Sam Robards; Jason Robards had five other children) — though arguably the actor’s greatest unions were with Eugene O’Neill, in the plays “The Iceman Cometh,” “Long Day’s Journey into Night” and “A Moon for the Misbegotten.”