Christopher Tolkien, son of legendary “The Lord of the Rings” author J.R.R. Tolkien, has died, the Tolkien Society reports. He was 95.

“Christopher Tolkien has died at the age of 95,” the org tweeted. “The Tolkien Society sends its deepest condolences to Baillie, Simon, Adam, Rachel and the whole Tolkien family.”

Christopher Tolkien has died at the age of 95. The Tolkien Society sends its deepest condolences to Baillie, Simon, Adam, Rachel and the whole Tolkien family. pic.twitter.com/X83PTx4b7x — Tolkien Society (@TolkienSociety) January 16, 2020

Christopher was Tolkien’s third son and was well known among his father’s fans. As he grew up, Christopher showed a great interest in his father’s work, eventually going on to edit and publish his unpublished material, including “The Silmarillion” in 1977 and “The Fall of Gondolin” in 2018. He was best known for publishing his father’s historical record of Middle-earth after his death in 1973.

Born in Leeds, United Kingdom, Tolkien served in the military, joining the Royal Air Force during World War II. After the war, he returned home to finish his studies in English at Trinity College in Oxford, later lecturing on Old English, Middle English and Old Icelandic at that same school.

Shaun Gunner, the chair of Tolkien Society, mourned Tolkien’s death on Twitter.

“As chair of @TolkienSociety this must surely be the very saddest day for me and all of us,” he wrote. “Christopher Tolkien was a titan of fantasy and his legacy will live on forever. Namárië #Tolkien.”

As chair of @TolkienSociety this must surely be the very saddest day for me and all of us. Christopher Tolkien was a titan of fantasy and his legacy will live on forever. Namárië #Tolkien https://t.co/iQ9iERuoZn — Shaun Gunner (@ShaunGunner) January 16, 2020

The Twitter account for Amazon’s upcoming “Lord of the Rings” series also paid tribute.

“Christopher Tolkien’s contributions to the world and to Middle-earth are incalculable. We are so grateful for his passion. He will be dearly missed,” they tweeted.

Christopher Tolkien’s contributions to the world and to Middle-earth are incalculable. We are so grateful for his passion. He will be dearly missed. — The Lord of the Rings on Prime (@LOTRonPrime) January 16, 2020

The Tolkien Estate has been overseen by his wife, Baillie Tolkien, and Tolkien’s grandson Michael George Reuel Tolkien.