In the history of archery, the title for most important invention probably goes to the English Longbowmen (or the Mongolian Recurve Bow which you can learn more about in the "Mongolian Fighting Tactics" episode). English Longbowmen brought about the end of the cavalry-dominated era and retained dominance over Europe for a period of around 300 years. Specifically, they allowed the English to dominate the French at the battles of Crecy (1346), Poitiers (1356), and Agincourt (1415). Though the English eventually lost the Hundred Years War, the English Longbowmen still made their mark.
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