Editing 900 (section)

=== By topic ===

==== Art ====
* c. 900 &ndash;[[1230]] &ndash; [[Pueblo Bonito]], [[Chaco Canyon]], [[New Mexico]], is built by the [[Ancestral Pueblo people]].

==== Religion ====
* January &ndash; Pope [[Pope John IX|John IX]] dies after a two year reign. He is succeeded by [[Pope Benedict IV|Benedict IV]] as the 117th [[pope]] of the [[Catholic Church]].<ref>Artaud de Montor [https://books.google.com/books?id=-JwAAAAAcAAJ&pg=PT62 ''Histoire des souverains pontifes romains''] Didot, 1846</ref>

==== Commerce ====
* The east coast of [[Africa]] is impacted by [[trade]] and Arab, [[Iran|Persian]] and [[India]]n traders mix with the indigenous [[Bantu peoples|Bantu]]. Many of the coastal Bantu adopt [[Islam]], reaching as far south as [[Sofala]] ([[Mozambique]]).

==== Exploration ====
* [[Greenland]] is discovered by the Norseman [[Gunnbjörn Ulfsson]], sailing from [[Norway]] to [[Iceland]]: he is blown off course by a [[storm]] and comes in sight of some [[Gunnbjörn's skerries|islands off the coast]] (approximate date).

==== Medicine ====
* The [[Persian people|Persian]] scientist [[Muhammad ibn Zakariya al-Razi]] distinguishes [[smallpox]] from [[measles]] in the course of his writings. Holding against any sort of orthodoxy, particularly [[Aristotle]]'s physics, he maintains the conception of an 'absolute' time, regarded by him as "a never-ending flow".
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