The presidency of Abraham Lincoln began on March 4, 1861, when he was inaugurated as the 16th President of the United States, and ended upon his assassination and death on April 15, 1865, 42 days into his second term. Lincoln was the first member of the recently-established Republican Party elected to the presidency. He was succeeded by Vice President Andrew Johnson. Lincoln presided over the Union victory in the American Civil War, which dominated his presidency. Lincoln presided over the Union victory in the American Civil War, which dominated his presidency. In December 1860, both the House and Senate formed special committees to address the unfolding crisis. Lincoln communicated with various Congressmen that there was room for negotiation on issues such as fugitive slaves, slavery in the District of Columbia, and the domestic slave trade. However he made it clear that he was unalterably opposed to anything which would allow the expansion of slavery into any new states or territories.