premise: The Hundred Years' War includes the Civil War.
hypothesis: Hundred Years' War . Local conflicts in neighbouring areas , which were contemporarily related to the war , including the War of the Breton Succession ( 1341 -- 1364 ) , the Castilian Civil War ( 1366 -- 1369 ) , the War of the Two Peters ( 1356 -- 1375 ) in Aragon , and the 1383 -- 85 Crisis in Portugal , were availed by the parties to advance their agendas . With respect to the belligerents , in France , civil wars , deadly epidemics , famines , and bandit free-companies of mercenaries reduced the population drastically . The dissatisfaction of English nobles , resulting from the loss of their continental landholdings , became a factor leading to the civil wars known as the Wars of the Roses ( 1455 -- 1487 ) .