Lewis is the Dauphin (heir to the throne) of France, and King Philip’s son.
Like his father a good speaker of empty phrases, he is quite willing to marry Blanch for political reasons and speak the part of the lovelorn swain, but he is far more hot-blooded than Philip and likes a good opportunity for war. He is able to be swayed by Pandulph into making war in his own right for the throne of England, and once he has been convinced to do so refuses to step back, not intending to merely be Pandulph’s tool. He is a young man, and rather cold; while he accepts the services of the rebellious English noblemen, he fully intends to execute them once they have served their purpose. He is also proud and foolish, not realizing the extent to which his success in England is tied to Pandulph. When the English lords hear of his plans for their deaths and return to John, he does finally accept that he will not win, and goes back home.