Ian McKellen wrote a moving tribute to Patrick Stewart, his close friend of many years, following his death Thursday at age 86 after suffering from Alzheimer’s and Lewy Body Dementia.

“Before everything else, Patrick was defined by being born and bred in Yorkshire, the proud county in the north of England which he loved to the end. You could hear it in his accented voice and in the stern honesty with which he told you what he thought and felt. Yorkshiremen have no truck with half-truths or avoidance of big issues. He wore his heart on his sleeve, which made him a man to rely on, to admire and in my case, love,” McKellen wrote on Instagram.

“We first met as ambitious young actors with the Royal Shakespeare Company half a century ago but we weren’t in the same productions. My first strong memory was a few years later, meeting him in the street in central London when he told me about an offer to take over a leading part in ‘Star Trek’. “But Patrick think of your stage career in the UK. Do you really want to risk — getting lost in Hollywood for years and years?” Well, he took the risk and thank goodness for us all that he did for not just his devoted Trekkies but film and theater audiences, who marveled at his using international celebrity to star in a string of cinema successes (‘X-Men‘ of course) and in great classical plays by Shakespeare, Ibsen, Arthur Miller, Peter Shaffer, Pinter and Beckett at Stratford-upon-Avon, in London’s West End and on Broadway.

“America was his adopted home, where he met his adored Sunny who has cared for him through sickness and health, through thick and thin. But he never forsook his origins: and the proudest achievement of the most respected and beloved actor of his generation on either side of the Atlantic, was his appointment as Chancellor of Huddersfield University in Yorkshire.”

“His farewell performance in ‘Avengers: Doomsday’ is yet to be seen,” McKellen concluded.

Stewart and McKellen’s friendship was one of the most beloved in the entertainment industry. The two became friends while playing Professor X and Magneto, respectively, in 2000’s “X-Men.” Looking back in a 2020 interview with Wired, Stewart said, “We had adjoining trailers. On those kind of movies, you spend more time sitting in your trailer than you do in front of the camera. So Ian and I hung out together, drinking tea — and maybe, in the afternoon, something a little stronger — and we got to know one another, and the charm of it was that we found we had so much in common.”

McKellen was the officiant when Stewart married his wife, Sunny Ozell, in 2013. “I’ll be frank with you — I’m in love with [him],” Stewart joked in the same interview. “But then, so is my wife in love with him, too, so that’s all right.” The friends made headlines several times over the years for so openly showing affection to each other, frequently kissing on the lips at red carpet events.

In addition to the original “X-Men” in 2000, Stewart and McKellen starred in in the sequels “X2” (2003) and “X-Men: The Last Stand” (2006), then made a cameo in “The Wolverine” (2013) before fully reprising their roles in 2014’s “X-Men: Days of Future Past.” Stewart also starred in 2017’s “Logan,” and both appear in “Avengers: Doomsday,” which will be released this December.

The pair has also worked together onstage, performing in a 2013 Broadway production of both Samuel Beckett’s “Waiting for Godot” and Harold Pinter’s “No Man’s Land” before doing “No Man’s Land” again in 2016 on London’s West End.