prologue
opening to a story that establishes the setting and gives background details or introductory scene, monologue preceding a play, or an introduction to a work, including musical work, or story in general
foreword
piece of writing sometimes placed at the beginning of a book or other piece of literature
Water Margin, Prologue
prologue of Water Margin, 120-chapter edition
Prologue
Snorri Sturluson's literary work
Loa
short play often performed before main play in Spanish Baroque theater
preface
introduction to a book or other literary work by the author
Concerning Hobbits
prologue to the novel The Lord of the Rings, by J. R. R. Tolkien