Lots of inaccurate statements to deal with here... Speculative entertainment about video game characters is one thing, but that was a total misrepresentation of history.
Sources:
The Viking Expansion - Climate, Population, Plunder http://scholarworks.umt.edu/cgi/viewcontent.cgi?article=4881&context=etd
https://www.skepticalscience.com/medieval-warm-period.htm
https://www.britannica.com/biography/Rollo-duke-of-Normandy
http://www.hurstwic.org/history/articles/manufacturing/text/viking_sword.htm#ulfberht
http://www.angelfire.com/wy/svenskildbiter/armsandarmour/mailshrt.html
Viking shield wall / testudo https://goo.gl/onwq4K
http://www.hurstwic.org/history/articles/manufacturing/text/viking_bow.htm
http://www.tameshigiri.ca/2014/04/10/the-asian-war-bow-the-physics-of-asian-archery/
http://www.vikingmartialarts.com/glima/
Shad's video response:
https://www.youtube.com/watch?v=18c3S7JiRNA&t=927s
Metatron's response:
https://www.youtube.com/watch?v=oTw_i9dBEmM&t=635s
https://www.ubisoft.com/en-US/game/for-honor
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