The question of "nationalism" is one of the big controversies for historians. Under this circumstances it is not easy to answer quickly without repeating the whole discussion, which is - and this will probably be a disappointment - a debate about the early modern period.

But going even back to the middle ages England and or France are actually not a bad example to get some grasp about medieval forms of national identity. Because the hundred years’ war sheds light on the late medieval notions of nationalism. Therefore, I want to try to answer the question using this topic as example. The conflict between France and England is in the beginning in the 14th century a matter of rank. The English king, because of his oversea holdings in France, is a vassal to the French king. At the same time the rise of the new Valois dynasty allowed the English kings to have a weak claim themselves to the French throne. This is in short the motivations and objectives for war between English and French in the beginning. It is argued by historians that while this conflict in essentially a conflict between related royal families and thus dynastic in its very nature. So no nationalist conflict from the start.

The further development of the hundred years war with military expeditions that devastated parts of France over several years, the expenses of both alliances involved, the casualties and economic destruction on both sides of the channel then together with the political struggle, that gained religious dimensions by the time of Joan of Arc, lead to a development of an early form of "nationalism". It must be clear that this is still not real "nationalism" as you would encounter it today. But in late medieval England in 15th century there was some sense of nation, as it is in the end of the development described above. On the French side this is even stronger one might argue.

Sadly, thou I must say that it might be debatable if people in the English countryside are more of a backwater to this development. The French peasantry definitely felt the destruction and terror of the war which often came in the form of looting soldiers of the "companies", marauding mercenaries and soldiers who didn’t got any more pay buy their employer and thus looted the countryside beyond their formers employers/overlords control.

The question of enrolling is interesting. Actually some of the rolls for mustering the troops survive today. Especially the English style of deployment, which relied on the combined army of archers and men at arms on foot in mostly defensive positions, was very much based on soldiers from a peasantry background (even thou this is not limited to archers but also to men at arms). This soldiers were paid soldiers and the army service was not really a “all must serve” thing. In Anne Curry’s book “Agincourt. a new history” from 2005 there is actually a list of all the known names of soldiers that fought on the English side in the battle 1415. This list contains around 7000 names, 1000 something of which are men at arms, the rest is archers. Still I want to reiterate that there was no real national service. Often there were militias for self-defense and people that were forced to serve if there was conflict near them. In general, we have to establish that troops in this kind of war were very small and only served for a limited time and far too often ruined the finances of the crowns that had to pay for their service. Even later in the war the French only had 6000 paid service men of standing army. There were no national armies with huge numbers of troops but smaller forces of soldiers that had very expensive equipment and only stayed in the field for limited times. The control was always limited and ineffitient, broadly speaking. The war in France and its effect on "civilians" is described in the books: Nicholas Wright, Knights and Peasants. The Hundred Years War in the French Countryside, Woodbridge 1998 and David Green, The Hundred Years War a People's History, Yale 2014.