Abraham Lincoln served as the
16th President of the United States from March 1861 until his assassination in April 1865. He successfully led his country through its greatest internal crisis, the
American Civil War, preserving the Union and
ending slavery. Before his election in 1860 as the first
Republican president, Lincoln had been a
country lawyer, an
Illinois state legislator, a member of the
United States House of Representatives, and twice an unsuccessful candidate for election to the
U.S. Senate. As an outspoken opponent of the expansion of
slavery in the United States,
Lincoln won the
Republican Party nomination in 1860 and was
elected president later that year. His tenure in office was occupied primarily with the defeat of the
secessionist Confederate States of America in the American Civil War. He introduced measures that resulted in the
abolition of
slavery, issuing his
Emancipation Proclamation in 1863 and promoting the passage of the
Thirteenth Amendment to the Constitution. Six days after the large-scale surrender of Confederate forces under General
Robert E. Lee, Lincoln became the first American president to be
assassinated.