Andrew Johnson (December 29, 1808 – July 31, 1875) was an American politician. He was the 17th President of the United States from 1865 to 1869. Before becoming president, he was the 16th Vice President of the United States. He became president after Abraham Lincoln was assassinated. He was the first president to be impeached, but he was not removed from office. The impeachment happened because he fired the Secretary of War after Congress had made it illegal. This was also considered strange, as it is usually up to the president to appoint and fire his secretaries. However, Congress disliked him because he was a Democrat and did not want to help former slaves.