William IV of the United Kingdom

William, Duke of Clarence, served in the Royal Navy from age 13, seeing action in the American Revolutionary War. He was stationed in New York and later served in the West Indies, earning the nickname 'Sailor King'.

Upon George IV's death, William became king at age 64. His accession was welcomed as a contrast to his brother's extravagance, and he quickly established a more informal, popular style of monarchy.

William IV reluctantly agreed to create enough Whig peers to pass the Reform Act 1832 in the House of Lords. The act reformed parliamentary representation, abolishing rotten boroughs and expanding the electorate.

William IV gave royal assent to the Slavery Abolition Act 1833, which abolished slavery throughout the British Empire. The act provided for a transition period and compensation for slave owners.

William IV dismissed the Whig government of Lord Melbourne, the last British monarch to remove a prime minister. He appointed Sir Robert Peel as prime minister, but Peel's minority government fell within months.