Abraham Lincoln was an American lawyer and statesman who served as the 16th president of the United States from 1861 until his assassination in 1865. Lincoln led the nation through the American Civil War and succeeded in preserving the Union, abolishing slavery, bolstering the federal government, and modernizing the U.S. economy.
On March 4, 1861, Abraham Lincoln was sworn in as president. In his inaugural address, he argued that the Constitution was a more perfect union than the earlier Articles of Confederation and Perpetual Union, that it was a binding contract, and called any secession "legally void".