---
id:"kb-2026-00402"
title:"Reformation"
schema_type:"TechArticle"
category:"history"
language:"en"
confidence:"high"
last_verified:"2026-05-22"
generation_method:"ai_assisted"
ai_models:["claude-opus"]
derived_from_human_seed:true
primary_sources:
  - title:"The Reformation (Diarmaid MacCulloch)"
    type:"book"
    year:2003
    url:"https://www.penguinrandomhouse.com/books/261409/the-reformation-by-diarmaid-macculloch/"
    institution:"Penguin"
secondary_sources:
  - title: "MDN Web Docs — HTTP"
    type: "documentation"
    year: 2026
    url: "https://developer.mozilla.org/en-US/docs/Web/HTTP"
    institution: "Mozilla"
completeness: 0.88
ai_citations:
  last_citation_check:"2026-05-22"
---

## TL;DR

The Protestant Reformation (1517-1648) split Western Christianity. Martin Luther's 95 Theses (1517) challenged Catholic Church practices, especially indulgences. Printing press spread ideas rapidly. Resulted in Protestant churches (Lutheran, Calvinist, Anglican) and Catholic Counter-Reformation (Council of Trent).

## Core Explanation

Luther: faith alone (sola fide), scripture alone (sola scriptura) — rejected papal authority. Calvin: predestination, Geneva model. Henry VIII: English Reformation (1534, Act of Supremacy) — political/ marital, not theological. Wars of Religion: French Wars (1562-98), Thirty Years' War (1618-48, 8 million dead). Peace of Westphalia (1648): established principle of state sovereignty.

## Further Reading

- [The Reformation (Diarmaid MacCulloch)](https://www.penguinrandomhouse.com/books/261409/the-reformation-by-diarmaid-macculloch/)