Ian Gelder, known for his role as Kevan Lannister in "Game of Thrones," has died at age 74 following a battle with bile duct cancer.

"It is with huge huge sadness and a heavy heart broken into a million pieces that I'm leaving this post to announce the passing of my darling husband and life partner Ian Gelder," actor Ben Daniels wrote Tuesday on Instagram.

"I'd stopped all work to be his carer, but neither of us had any idea that it would all be so fast. He was my absolute rock and we'd been partners for more than 30 years," Daniels wrote.

"If we weren't together we spoke to each other everyday. He was the kindest, most generous spirited and loving human being," he added.

"He coped with his dreadful illness with such bravery, with no self pity. Ever. He was remarkable and will be so missed."

Gelder's management agency confirmed his death on X, writing he was "such a lovely person and a wonderful actor," adding "he will be hugely missed by all those that loved him and worked alongside him."

Throughout his extensive career, the British actor portrayed multiple roles, including Mr. Dekker in "Torchwood: Children of Earth," and made notable guest appearances as Charles, the Librarian scholar in "His Dark Materials," and Zellin in "Doctor Who," the Independent reported.

However, it was his role in "Game of Thrones" that defined his career.

He first portrayed Kevan Lannister, the younger brother of Tywin Lannister, in the first season of the fantasy drama series. He would reprise the role in subsequent seasons throughout the HBO show. Most recently, he featured in an episode of the BBC One detective series "Father Brown" earlier this year.

Gelder was also known for his onstage work, delivering memorable performances in classic productions such as "The Crucible," "The Taming of the Shrew," and "The Front Page."

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