The book I can’t help thinking about right now is The Decameron. Penned by Giovanni Boccaccio at the dawn of the Renaissance, in street Italian rather than learned Latin, this doorstop tome incorporates 100 tales, or novelle, taken from a bewildering variety of far-flung sources, some dating back over a thousand years. Going forward, The Decameron would become a source in its own right. As retold by Boccaccio, the stories inspired greater and lesser lights for centuries, among them Chaucer, Shakespeare, and Keats.
The single best-known feature of The Decameron is its construction. The stories are told over the course of 10 days (as the title, from the Greek, implies). There are 10 narrators, seven women and three men collectively known as the brigata. Each day one of them presides as King or Queen, in which capacity all but two—Pampinea on Day I and Emilia on Day IX—dictate a narrative theme for all to follow.