He was the Count of Blois from about 830 and , at the time of his death in battle , was Louis 's constable .
William ( died 834 ) was a magnate in the Frankish Empire during the reign of his first cousin , Louis the Pious .
William was the Count of Blois from about 830 and , at the time of William 's death in battle , Louis the Pious Louis 's constable .
William ( died 834 ) was a magnate in the Frankish Empire during the reign of his first cousin , Louis the Pious .