The long, shared history of Christianity and Islam began in the early seventh century AD with a question: Who would inherit the Greco-Roman world of Mediterranean? Sprung from the same source, the two faiths played out over the millennium what historian Stephen O'Shea calls "a sibling rivalry writ very large." Their cataclysmic clashes on the battlefield were balanced by long periods of coexistence and mutual enrichment, and by the end of the sixteenth century the religious boundaries of the modern world were born.

O'Shea chronicles both the meeting of minds and the collisions of armies that marked the interaction of Cross and Crescent in the Middle Ages-the better to understand their apparently intractable conflict today.

Stephen O'Shea is an historian and the acclaimed author of Sea of Faith: Islam and Christianity in the Medieval Mediterranean World, The Perfect Heresy: The Revolutionary Life and Death of the Medieval Cathars, and Back to the Front: An Accidental Historian Walks the Trenches of World War I. Born in Toronto, he now lives in Providence, Rhode Island, and France.

Stephen O'Shea's profile page

"O'Shea's talent for enlivening 1,000-year old events, and his personal perspective on the modern landscape where all this history happened, help the larger story move along at a crackling pace. This is fascinating and readable."

Quill & Quire

"In this elegant, fast-paced, and judicious cultural and religious history, journalist O'Shea...provides a remarkable glimpse into the origins of the conflicts between Christians and Muslims as well as their once peaceful coexistence."

Publishers Weekly