I was reading an interesting answer on Quora about Mongol strategy when a battle description caught my eye:
Seeing this, the archbishop spurred his on his horse and gave them chase. Eventually, they reached a marshland and they crossed it swiftly. The archbishop did not notice this when he was quite close to them and hastily entered it. Being weighed down by their armor, he and his men could neither cross nor return. But the Tatars turned around quickly, surrounded the marsh, and killed them all with a shower of arrows. The archbishop escaped with three or four men and returned embossed to the city, quite irate because of the loss of his men and that the king did not send any help to them
by Rogerius of Apulia
My understanding was that the main Mongol invasion of Europe happened in the 1240s, when full-body plate armor was not widespread (that only happened toward the middle of the next century). Still, it looks like the Mongols did face plate armor… but of what quality?
Another problem was the relative softness of European plate armor made outside Italy. In the 15th century, the best plate armors were made in Italy and after that South Germany… Some Italian armor samples contain higher carbon content than armor from the rest of Europe, which increased their hardness. The English longbowman couldn’t penetrate the armor of Milanese knights in the Battle of Verneuil.
Armor from the rest of Europe… was often low carbon steel or wrought iron and often not hardened. Some plate armor could have a softness just above 100 VPH, which was as hard as work-hardened copper.
The Mongols of the 13th century would harden their arrowheads in saltwater. This would increase their likelihood of penetrating European armor.
So… arrows shot from galloping horses capable of penetrating even plate armor? Even given the plate armor’s poor quality, surely this can’t be right. Chainmail would probably stop arrows, right?
Erm, no. Turns out, it doesn’t. Not only that, but arrows were used nothing like we think today, as expert archer Lars Andersen demonstrates in the following video. From the proper way to hold your arrows to their piercing power, prepare to be amazed… and rewrite your fight scenes to reflect this new knowledge!