Assize of Arms
1. Let every holder of a knight's fee have a hauberk, a helmet, a shield and a lance. And let every knight have as many hauberks, helmets, shields and lances, as he has knight's fees in his demise.
2. Also, let every free layman, who holds chattals or rent to the value of 16 marks, have hauberk, a helmet, a shield, and a lance. Also, let every free layman who holds chattals or rent worth 10 marks have an aubergel and a headpiece of iron and a lance....
4. Moreover, let each and every one of them swear before the feast of St. Hilary he will possess these arms and will bear allegiance to the lord king, Henry, namely the son of empress Maud, and that he will bear these arms in his service according to his order and in allegiance to the lord king and his realm..."
From Webster's Online Dictionary, since the Assize of Arms of 1252 is nowhere to be found online:
"citizens, burgesses, free tenants, villeins and others from 15 to 60 years of age" should be armed. The poorest of them were expected to at least have a bow. This made it easier for the King to raise an army, but also meant that the bow was a commonly used weapon by rebels during the Peasants' Revolt. From the time that the yeoman class of England became proficient with the longbow, the nobility in England had to be careful not to push them into open rebellion. This was a check on the power of the nobility of England which did not exist on the European continent.
Medieval England understood the benefits of an armed population. The nation could be defended and the people would be more protected from tyranny.