King Henry I of England, born in 1068, was the fourth son of William the Conqueror. He became king in 1100 after the death of his brother, William II. Henry is known for his efforts to strengthen the monarchy and improve the administration of justice. He introduced the use of the Exchequer to manage finances and established a more organized legal system. Henry I's reign lasted until his death in 1135. He was married to Matilda of Scotland and had several children, but only one legitimate son, William Adelin, who died young. His death led to a succession crisis, sparking a civil war known as the Anarchy.