The year of the four emperors: Did you mean...?

Terracotta tablet listing the year formulae of King Shulgi of Ur. From Southern Mesopotamia, modern-day Iraq, Ur III period, 2094-2047 BCE. Ancient Orient Museum, Istanbul.

This map depicts the boundaries of all major civilizations in East Asia at the beginning of the Three Kingdoms Period of China, with italics indicating nomadic bands and other tribal...

This map shows the boundaries of all major civilizations in East Asia at the beginning of the first millennium, with italics indicating nomadic bands and other tribal societies.

This fragment of a clay tablet mentions certain formulas of naming years depending on major historical events. From Mesopotamia, modern-day Iraq. Early dynastic period, 2800-2300 BCE. The Sulaimaniya Museum...

A newspaper clipping from the Boston Gazette reporting on the funeral of four of the victims of the Boston Massacre, represented by an image of four coffins, each bearing the initials of a victim. These...

Christopher Columbus (c. 1451–1506) led four transatlantic expeditions between 1492 and 1504 under the patronage of Isabella I of Castile and Ferdinand...

The French Republican calendar, also known as the French Revolutionary calendar, was created during the French Revolution (1789-1799) in an attempt to build a new society separate from the vestiges of the Ancien Régime...

The Virgin of Guadalupe with the Four Apparitions, painting by Nicolás Enríquez, Mexico, 1773. This image depicts Our Lady of Guadalupe, an image of the Virgin Mary specific to Mexico/New Spain and her...

This map illustrates the four major khanates that emerged from the Mongol Empire in the early 14th century, following the fragmentation of the vast domain once ruled by Genghis Khan (circa 1162 to...

A map of the four Khanates of the Mongol Empire, after its division in 1259 CE.