General World History Links:

History: Academic Info
HistoryWorld
The Encyclopedia of World History
Women in World History
World History
World History Archives
World History: Hyper History Online
World Wide Virtual Library: History

Ancient China:

Ancient China
Chinese History
History of China
The Rise of Ancient China

Ancient Greece:

Ancient Greece
AncientGreece.com
BBC Schools - Ancient Greece
Maecenas: Images of Ancient Greece and Rome
The Ancient Greek World
The Perseus Digital Library

Ancient Rome:

Forum Romanum
Imperium Romanum
LacusCurtius: Into the Roman World
Roman Empire
Romans
Rome - History
Rome - Republic to Empire
The Gladiator
The Roman Empire

Medieval Times:

Internet Medieval Sourcebook
Medieval and Renaissance History
Medieval Europe
NetSERF
The Labyrinth: Resources for Medieval Studies

Islam:

About the Prophet Muhammad
BBC: Islam
Internet Islamic History Sourcebook
Islam
Islamic History
Islamic History in Arabia and the Middle East

The Renaissance:

Academic Info: The Renaissance
Art History: 15th Century Renaissance Art
La Renaissance
Medieval and Renaissance History
Renaissance
The Italian Renaissance Art Project