William IV was the third son of George III and brother of George IV. At the age of 13, he became a midshipman and began his career in the Royal Navy. He retired from the Navy in 1790 as the Duke of Clarence, and became heir apparent at the age of 62 when his older brother died. William's reign was dominated by the Reform crisis, leading to the Reform Bill. It eradicated some of the worst abuses of the electoral system, introduced standardised rules for the franchise and extended the franchise to the middle classes. He died a month after his niece, Victoria, had come of age.