The Hundred Years War had a devastating impact on the peasantry in both England and France. In France, the war led to widespread destruction of agricultural land, causing famine and displacement of rural populations. The English peasantry, meanwhile, faced increased taxation to fund the war, contributing to economic hardship and social unrest, as evidenced by the Peasants' Revolt in 1381. The war also accelerated changes in feudal relationships, as the need for large armies led to a shift from feudal levies to paid soldiers, reducing the peasantry's feudal obligations but also their traditional social securities.

The Hundred Years War played a crucial role in the development of national identities in England and France. In England, the war fostered a sense of national unity against a foreign adversary, reinforcing English identity. In France, the struggle against English invasion unified the French territories and people under the banner of defending their homeland. This sense of shared purpose and identity was instrumental in the development of the modern concept of the nation-state. The war also contributed to the creation of national myths and heroes, further solidifying national identities in both countries.

The Treaty of Brétigny, signed in 1360, was a significant moment in the Hundred Years War. It marked a temporary halt in hostilities and led to substantial territorial and financial concessions from France to England. Under this treaty, France ceded a large part of its territory, including Aquitaine, to England and agreed to pay a large ransom for the release of King John II. However, the treaty’s terms were not fully implemented, leading to the resumption of the war in 1369. It represented a high point of English success but also reflected the fragile and temporary nature of peace during this period.

The long-term consequences of the Hundred Years War on European politics and society were profound. The war marked the decline of feudalism and the rise of centralised state power, particularly in France and England. This shift laid the groundwork for the modern nation-state system in Europe. The conflict also led to significant social and economic changes, including the decline of the knightly class and the rise of professional armies. Additionally, the war's impacts on trade and commerce contributed to the development of a more market-oriented economy, setting the stage for the eventual rise of capitalism in Europe.

Notable military leaders had profound impacts during the Hundred Years War. Edward, the Black Prince, demonstrated exceptional leadership and military tactics, especially at the Battle of Poitiers where his strategy led to the capture of the French King John II. On the French side, Bertrand du Guesclin played a crucial role in the latter phase of the war. His adoption of guerrilla warfare tactics significantly undermined the English army's effectiveness. These leaders exemplified the shift in military strategy during this period, from traditional chivalric warfare to more modern, innovative approaches.