How did two men cause the hundred years' war? a). the british king edward lll first invaded france to claim he was king of not only england, but france as well. b). france's king phillip vl snatched land from king edward lll and retalliation had to follow. c). two leaders with power trying to out-do each other. d). actually not consistent 100 years of war but a series of conflicts, the time span was under 100 years.