What was one way the Hundred Years' War affected England? England's king grew in power.
England became a unified nation.
England's military became very powerful.
England lost all of its land on the European continent.

Hundred Years’ War, an intermittent struggle between England and France in the 14th–15th century over a series of disputes, including the question of the legitimate succession to the French crown. The struggle involved several generations of English and French claimants to the crown and actually occupied a period of more than 100 years. By convention the war is said to have started on May 24, 1337, with the confiscation of the English-held duchy of Guyenne by French King Philip VI. This confiscation, however, had been preceded by periodic fighting over the question of English fiefs in France going back to the 12th century.

Explanation:

I found this answer online. I hope you find this answer helpful, though.