Henry Percy, Earl of Northumberland
A rebel, Northumberland is a member of the Percy family and the father of Hotspur. He played a significant role helping King Henry to the crown in Richard II and in Henry IV Part 1 is disgruntled with the new king. Northumberland takes part in plotting the rebellion against Henry, but when push comes to shove, he phones in sick and leaves his son hanging. His failure to show at the battle at Shrewsbury reminds us that fathers can't always be trusted to protect their children.