John Calvin 1509–64, French Protestant theologian of the Reformation, b. Noyon, Picardy.

As a persecuted Protestant, Calvin found it necessary to travel from place to place, and at Angouleme in 1534 he began the work of systematizing Protestant thought in his Institutes of the Christian Religion, considered one of the most influential theological works of all time. Completed at Basel in 1536 and later frequently revised and supplemented, the original work contained the basic Calvinist theology. In the Institutes Calvin diverged from Catholic doctrine in the rejection of papal authority and in acceptance of justification by faith alone, but many of his other positions, including the fundamental doctrine of predestination, had been foreshadowed by Catholic reformers and by the Protestant thought of Martin Luther and Martin Bucer.

The old Catholic church -- long adjusted to the medieval, feudal order of the agrarian countryside -- was totally out of touch spiritually with the new breed of urban Europeans who were growing up in northern Europe.  Though Luther had broken the power of the decaying church in the German countryside, it was Calvin who carried the "Reformed" gospel to the European cities of Northern Europe -- by developing the city of Geneva, Switzerland, as the model and example of Christian living in a newly emerging urban culture.  Reformers flocked from all over European towns and cities to Geneva in order to study and learn about the meaning of Christ's way in a culture that had moved on beyond the old rural feudal system.

The extension of Calvinism to all spheres of human activity was extremely important to a world emerging from an agrarian, medieval economy into a commercial, industrial era. Unlike Luther, who desired a return to primitive simplicity, Calvin accepted the newborn capitalism and encouraged trade and production, at the same time opposing the abuses of exploitation and self-indulgence. Industrialization was stimulated by the concepts of thrift, industry, sobriety, and responsibility that Calvin preached as essential to the achievement of the reign of God on earth. The influence of Calvinism spread throughout the entire Western world, realizing its purest forms through the work of John Knox in Scotland and through the clergymen and laymen of the civil war period in England and the Puritan moralists in New England.