John Barton, co-founder of the Royal Shakespeare Company and director of more than fifty productions there, has died at age eighty-nine, according to the RSC. Artistic director Gregory Doran posted a touching eulogy on the company’s website not long after Barton died last Thursday.

“John was… simply one of the greatest influences in the acting of Shakespeare of the last century,” Doran wrote, praising his colleague’s “ability to uncover the clues that Shakespeare wrote into the text to enable actors to deliver it with freshness and vivid clarity.”

Barton oversaw many productions at the RSC, defining how both particular Shakespeare plays and particular actors are perceived. Highlights include a 1969 production of Twelfth Night that starred Judi Dench, and two very popular iterations of The Merchant of Venice, with Shylock played by Patrick Stewart in 1978, and later by David Suchet in 1981.

But he is perhaps best known, along with RSC co-founder Peter Hall (who died last year), for the epic The Wars of the Roses, the combination of four of Shakespeare’s histories—the Henry VI trilogy and Richard III—into a single performance. First staged in 1963, when the RSC was just a few years old, The Wars of the Roses incorporated the political realities of the 1960s into its over-eight-hours-long adaptation, with Barton writing 1,400 new lines of dialogue (and cutting over 12,000) for the production, as Hall and Barton write in the 1970 publication of their adaptation.

The production was a critical and commercial success — a staggering accomplishment for an hours-long theatrical event. Bernard Levin, writing in the Daily Mail, called it “a production of epic, majestic grandeur, a landmark and a beacon in the post-war English theatre.” He also heralded it as “one of the mightiest stage projects of our time.” George Seddon offered similar praise in the Observer: “It was a stupendous day, even though one emerged from it sagging with physical and emotional exhaustion.”

Later on, Barton enjoyed more commercial success with his “Playing Shakespeare” series, recorded by ITV’s London Weekend Television. Broadcast throughout the eighties, the series influenced an entire generation of actors — and helped cement the careers of such thespians as Roger Rees, Ian McKellen, Peggy Ashcroft, and Ben Kingsley. Barton also wrote the accompanying guide to the series, which is still in print. He was appointed to the Order of the British Empire in 1981, and received the Sam Wanamaker Award in 2001.

Patrick Stewert tweeted out a brief remembrance on Thursday, stating that “the names William Shakespeare and John Barton will be for me forever united.” Stewart also wrote about Barton’s death and its impact on him in a eulogy printed by the Guardian. “He showed me the landscape of great writing and the place performance had in it,” Stewart wrote. “He touched everything in my career.”

The RSC’s autumn production of Troilus and Cressida, Barton’s favorite play, will be dedicated to the co-founder. “I regret that he won’t be around to tell me what I got wrong,” Doran writes.