 Charles VI 's uncle , Philip the Bold , Duke of Burgundy , thought the proposed marriage ideal to build an alliance with the Holy Roman Empire and against the English . Isabeau 's father agreed reluctantly and sent her to France with his brother , her uncle , on the pretext of taking a pilgrimage to Amiens . He was adamant that she was not to know she was being sent to France to be examined as a prospective bride for Charles , and refused permission for her to be examined in the nude , customary at the time . According to the contemporary chronicler Jean Froissart , Isabeau was 13 or 14 when the match was proposed and about 16 at the time of the marriage in 1385 , suggesting a birth date of around 1370 . 
