War of 100 Years,many nobles died in these series of battles,but.."gentlemen of England lie on beds.",the citizens had rised;
afterwards war of Rose was not only a succession war,but a civil war of feudal nobles,thousands of noblemen and their esquires died,while citizens of towns,craftmen,mechants were seldom affected by this war.
the great plague "black death",was not simply a natural disaster,but also a impulse of society,20% or more of English population has been declined,ternants had more choices on whom they work for,wage capitals are raised,landlords were forced to paticipate competition and changed their ways of income.
such context are partial reasons,more reason can be the rise of mechanism,concentration of political power,rise of royal sovereignty,the English church reform,Acts of Supermacy 1534.etc.