The biggest myth is that the longbow was an English weapon wielded by English archers. It was in fact a Welsh weapon wielded in the main at Agincourt, Crecy, and Poitiers, by Welsh archers (albeit in the service of the English army).
You got me there! My American background failed me in that respect. In the US there was lots of competition between the Virginians vs the New Yorkers vs the Vermonters vs the Bostonians, etc etc. But in the end we (generally) always saw ourselves as Americans first, and Virginians, New Yorkers, etc second. It keeps escaping me that "English" is not the same as "Welsh" nor the same as "British". (English and Welsh are surely both British, right, or have I got that wrong? And Ireland and Scotland are also British?)