Reformed Founders

Who founded Reformed theology?

The Reformed tradition had many founders. Its founding documents run from 1523, when Huldrych Zwingli published his 67 Articles in Zurich, to 1566, when Heinrich Bullinger’s Second Helvetic Confession appeared.1

It happened in Zurich, Strasbourg, Geneva, and Scotland. John Calvin was 22 when Zwingli died. He later learned how to run a city church from Martin Bucer in Strasbourg, reached an agreement with Bullinger in 1549 (the Consensus Tigurinus), and founded the Geneva Academy with Theodore Beza in 1559.2

This site introduces 6 of those founders, what they taught, and short passages in their own words. Every date and quote links to a source you can check.

The founders

Listed by birth year.

  • Huldrych Zwingli (1484-1531) · Zurich. Led the Swiss Reformation and founded the Swiss Reformed Church.
  • Martin Bucer (1491-1551) · Strasbourg. Spent decades trying to reconcile rival reform movements. Calvin learned from him.
  • Heinrich Bullinger (1504-1575) · Zurich. Zwingli’s successor, and author of the Second Helvetic Confession.
  • John Calvin (1509-1564) · Geneva. Wrote the Institutes of the Christian Religion and shaped the church in Geneva.
  • John Knox (c. 1514-1572) · Scotland. The foremost leader of the Scottish Reformation.
  • Theodore Beza (1519-1605) · Geneva. First rector of the Geneva Academy, and Calvin’s successor.3

What “Reformed” means

Britannica dates the beginning of the Reformed tradition to 2 agreements led by Bullinger: the Consensus Tigurinus with Calvin (1549) and the Second Helvetic Confession (1566). It describes the tradition as “the fusion of Zwinglian and Calvinist thought.”4

So is “Reformed” the same as “Calvinism”? They overlap. “Calvinism” names Calvin’s interpretation of Christian teaching, which Britannica calls characteristic of Reformed churches.5 “Reformed” is the wider name for the tradition, which also carries Zwingli’s and Bullinger’s work from Zurich. When Calvin reached Geneva in 1536, Zwingli had published his 67 Articles 13 years earlier.

Where to start

  • New to this? Start with John Calvin, the best-known founder.
  • Want the big picture? See how they connect, from Zwingli’s 67 Articles to Beza’s death in 1605.
  • Want to read them yourself? Every founder is free to read in public-domain editions.

By Casey Case · Sources last checked September 26, 2026

Sources

  1. Britannica, “Huldrych Zwingli” and “Heinrich Bullinger,” accessed Sept. 26, 2026. ↩︎
  2. Britannica, “John Calvin,” “Heinrich Bullinger,” and “Theodore Beza,” accessed Sept. 26, 2026. ↩︎
  3. Dates and roles from Britannica’s articles on Zwingli, Bucer, Bullinger, Calvin, Knox, and Beza, accessed Sept. 26, 2026. ↩︎
  4. Britannica, “Heinrich Bullinger,” accessed Sept. 26, 2026. ↩︎
  5. Britannica, “John Calvin,” accessed Sept. 26, 2026. ↩︎