Ian McKellen is honoring his longtime close friend Patrick Stewart in a heartfelt tribute.

On Thursday (October 29), McKellen, 87, shared a lengthy post on Instagram celebrating his X-Men costar's life and legacy following the actor's death at age 86 on Wednesday.

"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," he said. "You could hear it in his accented voice and in the stern honesty with which he told you what he thought and felt. Yorkshire men 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 recalled first meeting Stewart "half a century ago" when they were both "ambitious young actors with the Royal Shakespeare Company," though they weren't in the same productions at the time. He even shared that he once urged Stewart to be wary of starring in Star Trek and how Stewart's decision not to follow his warning only aided in his storied career.

"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?'" he recalled telling his friend. "Well, he took the risk and thank goodness for us all that he did for not just his devoted Trekkies but film and theatre audiences, who marvelled 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 Statford-upon-Avon, in London's West End and on Broadway."

He continued, "America was his adopted home, where he met his adored [wife] 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."

Stewart's longtime spokesperson Kelly Bush Novak confirmed on Thursday that he had passed away at his home in Los Angeles after "a brief and poignant journey with Alzheimer's Disease and Lewy Body Dementia," according to The Hollywood Reporter.

"He has been held in the warm embrace of family and friends, surrounded by live music, prayer, tears, laughter and the kind of profound emotion that only he could inspire after a lifetime of devotion to us all. We will forever cherish the peaceful ease and reflection on his face, an enduring reminder of his invincible grace."