Richard Dysart -- a veteran of stage and screen best known for his role on "L.A. Law" -- died Sunday after a long battle with cancer. He was 86.

According to Dysart's daughter-in-law, he passed away at his home in Santa Monica. His wife tells us he'd been diagnosed with cancer a few years ago.

Dysart had a penchant for playing famous figures -- he portrayed Dwight D. Eisenhower (twice), J. Edgar Hoover (twice) and Harry Truman (twice). He also famously played the villain against Clint Eastwood in "Pale Rider."

But he became a household name as Leland McKenzie on "L.A. Law," which ran from 1986-1994. He was nominated for four Emmys, winning once in 1992.

He won a Drama Desk Award in 1972 for originating the role of The Coach in That Championship Season on Broadway and was a founding member of the American Conservatory Theatre, San Francisco. He also had many film credits including the horror class The Thing, Clint Eastwoord’s Pale Rider, Ashby’s Being There, and even a small role in Back to the Future Part III.

Dysart was born on March 30, 1929 in Boston. He served four years in the Air Force during the Korean War.