In what year was income tax first introduced in the UK?

Income tax was first introduced in the UK in 1799, during the Napoleonic Wars. The British government needed to raise funds to finance the war effort, and income tax was seen as a fair and efficient way to generate revenue. It was initially a temporary measure, but it was reintroduced in 1842 as a permanent tax. Income tax has since become a significant source of government income and is still in place today.