The first war in recorded history was [between Sumer and Elam in 2700 BCE.] (http://www.ancient.eu/war/) However there is evidence of warfare all the way back to the Mesolithic era (sometime between 14,300 and 13,200 years ago) at a site near the border of Egypt and Sudan called [Cemetery 117.] (http://www.ancientworldreview.com/2014/07/the-skeletons-in-cemetery-117.html)

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