Which of J.R.R. Tolkien’s sons became the principal editor of his posthumously published works?

Christopher Tolkien became the principal editor of J.R.R. Tolkien’s posthumously published works.

Christopher Tolkien, J.R.R. Tolkien’s third son, edited The Silmarillion, which appeared in 1977, and later prepared many other volumes from his father’s papers. His editorial work included Unfinished Tales and the twelve-volume History of Middle-earth, published between 1983 and 1996.

The manuscripts often contained multiple versions of names, events, and passages written at different times. Christopher supplied introductions, notes, organization, and editorial decisions so that readers could understand how the legendarium developed and where texts remained unfinished or inconsistent.

Christopher was not the only member of Tolkien’s family involved with his legacy. John Tolkien became a Catholic priest, Michael and Priscilla also preserved family and literary history, and Christopher’s own editorial publications eventually included The Children of Húrin, Beren and Lúthien, and The Fall of Gondolin.