This is a history of the so-called "Monophysite" schism from the Council of Chalcedon to the Muslim conquest.

In this book, the Rev. William Ainger Wigram, head of the Mission of the Archbishop of Canterbury to the Assyrian Church, gives an introduction to the history of the ancient church, covering its Christology.

Rev. Wigram spent much of his clerical career working with the Church of the East, and for years after WWI, he spoke to English readers on behalf of the modern Assyrian people about their claims to a just settlement. This book is his last book on the subject.