I beg to differ, they were well acquainted with the "English Long Bow", most notably at Crécy (1346) when the English under the command of King Edward III and his son, the "Black Prince" Edward, defeated the French-led army of at least 3 times their number.
Henry V was King Edward's Great Grandson through John of Gaunt, brother of the "Black Prince". Shakespeare made reference to Crécy in the speech that the French King made to his nobles, reminding them of their disastrous loss then.
Quite right, I got French defeats mixed up. At Agincourt it was the muddy fields that slowed the French.