For a remarkably long period, from the inception of the Capetian dynasty in 987 until the death of Louis X in 1316, the eldest living son of the King of France succeeded to the throne upon his demise. There was no prior occasion to demonstrate whether or not females were excluded from the succession to the crown. Louis X died without a son, but left his wife pregnant. The king's brother, Philip, Count of Poitiers, became regent. Philip prepared for the contingencies with Odo IV, Duke of Burgundy, maternal uncle of Louis X's daughter and prospective heiress, Joan. If the unborn child was male, he would succeed to the French throne as king; if female, Philip would maintain the regency until the daughters of Louis X reach their majority. There was opportunity for either daughter to succeed to the French throne.