Through exposing the precursors of Protestantism, such as the Waldenses, and explaining how the Roman Catholic church had developed since the fall of the Roman Empire, Wylie is able to explain how mid-sixteenth century Europe became a hotbed of discussions on religion and the position of the Church of Rome.

He uncovers how the founding fathers from Luther and Hus to Calvin and Zwingli forged their churches under the oppression of the Roman Catholic leaders, and sometimes in conflict with other Protestant churches.

Wylie uncovers how different nations reacted to the advent of Protestantism through the sixteenth and seventeenth centuries, including Switzerland, France, Scandinavia, England and the multitude of German states in the Holy Roman Empire.

Protestantism had no centralized organization to define doctrine so across these varying regions differing churches developed. Wylie explains their different theological positions and why such differences arose.

The History of Protestantism is essential reading for anyone interested in how this faith broke with Rome and survived through its tumultuous first few centuries to develop into the religion that it is recognizable as today.