(1809-65) a US politician in the REPUBLICAN PARTY who was President of the US from 1861 to 1865. He won political support in the Northern US states because of his speeches against SLAVERY, but this made him unpopular in the Southern states, where slaves did most of the farm work. The American CIVIL WAR started soon after he became President, when the Southern states decided to leave the US. In 1863 he announced the EMANCIPATION PROCLAMATION, by which all slaves in the US became free people. He also gave a famous speech known as the GETTYSBURG ADDRESS in 1863. A few days after the war ended, he was shot and killed in a theatre by an actor called John Wilkes BOOTH . Lincoln is one of the most important US presidents, and was sometimes called 'Honest Abe' because everyone admired his honesty.