Patrick Stewart, the acclaimed British actor known for his iconic roles in the Star Trek and Marvel franchises, died at the age of 86 in his Los Angeles home on Wednesday local time. His passing followed a brief battle with Alzheimer’s disease and Lewy Body dementia.

Stewart rose to international fame with his portrayal of Captain Jean-Luc Picard in the television series Star Trek: The Next Generation, a role he first took on in 1987 at age 47. Originally expecting the series to last only one season, Stewart’s performance helped the show gain a significant following and established him as a prominent figure in science fiction television. Later, he reached an even wider audience playing Professor Charles Xavier, also known as Professor X, in the Marvel Cinematic Universe. Audiences saw Stewart repeatedly bring the character to life in films such as X-Men: The Last Stand, Logan, Multiverse of Madness, and the upcoming Avengers: Doomsday, which will serve as his final on-screen appearance.

Marvel Studios president Kevin Feige paid tribute to Stewart, highlighting his brilliance, warmth, and generosity both on and off screen. Feige called Stewart’s legacy enduring, noting his impact through decades of work and his mentorship of numerous individuals in the industry.

Stewart’s contributions extended beyond his acting career. An announcement on his Instagram page emphasized his dedication to philanthropy and activism, particularly supporting human rights, survivors of domestic violence, global refugees, veterans’ mental health, and animal welfare. Stewart’s advocacy for survivors of domestic violence was deeply personal; he grew up in a working-class Yorkshire family where he witnessed his father’s abuse of his mother after returning from World War II.

Before his rise to stardom, Stewart worked as a journalist and later forged a long and successful career on both stage and screen. His contributions to drama were recognized with a knighthood from Queen Elizabeth II in 2010.

Tributes have poured in from colleagues and peers. William Shatner, who portrayed Captain James T. Kirk in the original Star Trek series, honored Stewart on social media, describing him as a figure who “stood for the best of us.” Actor Hugh Jackman, who worked with Stewart in Logan, remembered him as “one of the greats of stage and screen” and a “tremendous friend.”

Patrick Stewart will be remembered for his dignity, compassion, and humanity, qualities that defined both his professional career and personal life.