Which posthumously published Tolkien work presents the myths of Arda?

The Silmarillion presents the myths and history of Arda in a work published after J.R.R. Tolkien’s death.

Christopher Tolkien edited the material and published The Silmarillion in 1977, four years after his father died. The book is not a conventional single narrative. It gathers creation myths, legends, genealogies, and historical accounts describing the development of Tolkien’s fictional world from its beginnings through the First Age and beyond.

Its opening section, the Ainulindalë, describes the creation of the world through music. The Valaquenta introduces the powerful spirits called the Valar and Maiar. The Quenta Silmarillion then focuses on the history of the Silmarils and the conflicts involving Elves, Morgoth, and Men.

The title can mislead readers who expect another adventure centered on the Silmarils alone. The book also contains the Akallabêth, about Númenor, and “Of the Rings of Power and the Third Age,” which connects its mythology to The Lord of the Rings.