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World History Reference — Verified Entries, Sources & Timelines

Today's Featured Entry · Wednesday, 22 January 2026

The Treaty of Westphalia, 1648

By Dr. M. Castelló, Editorial Board · Reviewed by Prof. H. Aldridge (Yale)

Concluded on 24 October 1648 at Münster and Osnabrück, the Peace of Westphalia ended the Thirty Years' War and, with it, the Holy Roman Empire's last coherent claim to enforce religious conformity across its territories ^[1]^[2]. The treaty's recognition of the Dutch Republic and the Swiss Confederation as sovereign states, and its grant of cuius regio, eius religio to the imperial estates, marks the conventional turning point between the medieval and early modern periods in European historiography ^[3].

Westphalia is frequently invoked as the origin of the modern state system; this claim is supported in much mainstream scholarship but contested in revisionist literature of the past two decades ^[4].

Confidence: High — 4/4 independent sources concur. Sources cited: Treaty of Osnabrück (1648); Croxton, Westphalia: The Last Christian Peace (2013); Wilson, The Thirty Years War: Europe's Tragedy (2009); Osiander, "The States System of Europe, 1640–1750" (1994).

The Comparative Timeline

Overlay four centuries of history on a single axis.

Scrubbable. Comparative. Exportable to Chicago, MLA, or APA in one click.

Archival reading table with an open historical atlas — Plate I — A working surface for the comparative timeline, photographed in the editorial reference room.

Four lanes. One axis.

Wars & conflict1,240 events
Science & technology880 events
Art & architecture2,410 events
Politics & reform1,975 events

Toggle lanes on or off to surface only the events relevant to your essay. Any view exports as a citation-ready figure.

Open the Timeline

Editorial Method

How an entry earns its citations.

Four passes, four pairs of eyes, a minimum of three independent sources before a single sentence ships.

01
Research

Scoped against the historiographical literature by a research associate with subject-matter training.
02
Draft

Written by a trained editor to a house style that foregrounds inline citation, date ranges, and named polities.
03
Verify

Reviewed by a credentialed historian on our 41-person editorial board — including 6 former university department chairs.
04
Cross-reference

Every claim checked against at least three primary or peer-reviewed sources, then assigned a confidence rating.

Verified by Dr. M. Castelló, MIT · Prof. H. Aldridge, Yale · Dr. R. Onyeka, SOAS · Prof. L. Behrens, Heidelberg

Scope · January 2026

312 civilizations. 4,200 years. One index.

From the Olmec heartland to the Ottoman reform commissions of the nineteenth century — nameplates grouped loosely by era.

Olmec jade figurine on a museum mount — Plate II — Olmec, c. 1200–400 BCE.

Bronze AgeOld Kingdom Egypt
Bronze AgeSumer & Akkad
Bronze AgeMinoan Crete
Bronze AgeShang Dynasty
Bronze AgeHittite Empire

ClassicalAchaemenid Persia
ClassicalHan Dynasty
ClassicalRoman Republic
ClassicalMaurya & Gupta
ClassicalMaya City-States

Cuneiform clay tablet fragment — Plate III — Cuneiform fragment, Neo-Babylonian period.

MedievalByzantine Empire
MedievalMali Empire
MedievalTang Dynasty
MedievalCaliphate of Córdoba
MedievalMongol Khanates

Early ModernOttoman Reforms
Early ModernMughal India
Early ModernSpanish Habsburgs
Early ModernEdo Japan
Early ModernQing Dynasty

ModernMeiji Restoration
ModernWeimar Republic
ModernDecolonisation
ModernPan-African Congresses
ModernUnited Nations System

Stack of aged leather-bound reference books — Plate IV — Working library, 2025 reference shelf.

Coverage drawn from mainstream scholarship; revisionist or contested framings are clearly labeled at the entry level.

House Standard

No statement enters the index without at least three independent primary or peer-reviewed sources behind it, mainstream scholarship as its default, and disputed claims labeled as such — by name.

Editorial Board, HistoryKB · Cambridge, MA

The structured knowledge base for world history — verified timelines, primary sources, and citation-grade context across every civilization.

The Treaty of Westphalia, 1648

Overlay four centuries of history on a single axis.

Four lanes. One axis.

How an entry earns its citations.

Research

Draft

Verify

Cross-reference

312 civilizations. 4,200 years. One index.