William IV of the United Kingdom, born on August 21, 1765, was the third son of King George III. He became king in 1830 after the death of his brother, King George IV. Known as the "Sailor King," William had a naval career before ascending the throne. His reign lasted until 1837 and was marked by significant political reforms. During his time as king, William IV supported the passage of the Reform Act of 1832, which expanded the electorate and reformed the electoral system. He was also known for his efforts to improve the conditions of the working class and for his opposition to slavery, which was abolished in the British Empire during his reign.