By Elma Aksalic

British actor Sir Patrick Stewart, best known for his roles in the “Star Trek” franchise and “X-Men” films, has died at age 86.

Stewart died on Oct. 28 at his home in Los Angeles, according to his longtime spokesperson Kelly Bush Novak. He had been living with Alzheimer’s disease and Lewy body dementia.

With a career spanning more than six decades, millions came to know him as Captain Jean-Luc Picard in “Star Trek: The Next Generation,” but his roots began in the theater.

Born in 1940, in Mirfield, Yorkshire, England, Stewart developed his craft through classical training and, in 1966, joined the Royal Shakespeare Company, where he spent years performing the works of Shakespeare and other major playwrights.

His international breakthrough came in 1987, when he was cast as Picard, commander of the starship Enterprise. Stewart’s performance helped establish the television series “Star Trek: The Next Generation.” He went on to reprise the character in feature films and the series “Star Trek: Picard.”

The Associated Press contributed to this report.