900

Millennium:	1st millennium
Centuries:	8th century – 9th century – 10th century
Decades:	870s  880s  890s  – 900s –  910s  920s  930s
Years:	897 898 899 – 900 – 901 902 903

900 Media

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  The Earth's Eastern Hemisphere (c. 900)

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  Gunnbjörn discovers Greenland (c. 900)

900 (CM) was a leap year starting on Tuesday of the Julian calendar, the 900th year of the Common Era (CE) and Anno Domini (AD) designations, the 900th year of the 1st millennium, the 100th and last year of the 9th century, and the 1st year of the 900s decade. As of the start of 900, the Gregorian calendar was 4 days ahead of the Julian calendar, which was the dominant calendar of the time.

Events

• Persian scientist, Rhazes, distinguished smallpox from measles in the course of his writings. Holding against any sort of orthodoxy, particularly Aristotle's physics, he maintained "the conception of an 'absolute' time, regarded by him as a never-ending flow".
• Gyeonhwon formally establishes the kingdom of Hubaekje in southwestern Korea.
• Merchants from southwest Asia and India settle on the east-African coast, trading gold, beads and metal for ivory and slaves.
• Harold I of the Yngling or Scilfing dynasty subdues the petty kings of Norway and conquers the Orkney and Shetland islands.