Who is Robert III of Artois from The Iron King and what is their importance?

Robert the Third of Artois is a giant of man, who once could have ruled the province of Burgundy in France, were it not for this region being granted to his aunt Mahaut for the hands of her daughters to the Princes of the realm. Robert Artois spends the rest of his life trying to correct this 'mistake' and seethes with anger towards his more distant relations.

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