This book explores the different peoples who inhabited the historical region of Eastern Arabia (al-Ba?rayn and Ka?ima) in the centuries before and during the rise of Islam. The book charts and relates the histories of the diverse peoples who called the region home, including Syriac Christians, Babylonian Jews, Persians, Indians, Indonesians and Arabian tribes. Using primary sources in Arabic, Syriac, Persian and Hebrew, as well as the latest archaeological evidence, the book reveals how each group was uniquely incorporated into the wider late antique world through religion, culture, politics and trade, and how each was affected differently by the rise of Islam. Providing a new perspective on the religious and cultural diversity of Arabia and on its regional connections prior and during the birth of Islam, the book will be of interest to scholars and students of Late Antiquity, Islamic history, Eastern Christianity, Arabian and Iranian studies.