This country, with its institutions, belongs to the people who inhabit it. Whenever they shall grow weary of the existing government, they can exercise their constitutional right of amending it, or exercise their revolutionary right to overthrow it.

Abraham Lincoln (February 12, 1809 – April 15, 1865) was the 16th President of the United States, serving from March 1861 until his assassination in April 1865. Lincoln led the United States through its Civil War—its bloodiest war and its greatest moral, constitutional, and political crisis. In doing so, he preserved the Union, abolished slavery, strengthened the federal government, and modernized the economy.

Born in Hodgenville, Kentucky, Lincoln grew up on the western frontier in Kentucky and Indiana. Largely self-educated, he became a lawyer in Illinois, a Whig Party leader, and a member of the Illinois House of Representatives, where he served from 1834 to 1846. Elected to the United States House of Representatives in 1846, Lincoln promoted rapid modernization of the economy through banks, tariffs, and railroads. Because he had originally agreed not to run for a second term in Congress, and because his opposition to the Mexican–American War was unpopular among Illinois voters, Lincoln returned to Springfield and resumed his successful law practice. Reentering politics in 1854, he became a leader in building the new Republican Party, which had a statewide majority in Illinois. In 1858, while taking part in a series of highly publicized debates with his opponent and rival, Democrat Stephen A. Douglas, Lincoln spoke out against the expansion of slavery, but lost the U.S. Senate race to Douglas.

In 1860, Lincoln secured the Republican Party presidential nomination as a moderate from a swing state. With very little support in the slaveholding states of the South, he swept the North and was elected president in 1860.

When I am getting ready to reason with a man, I spend one-third of my time thinking about myself and what I am going to say and two-thirds about him and what he is going to say.

His victory prompted seven southern slave states to form the Confederate States of America before he moved into the White House – no compromise or reconciliation was found regarding slavery and secession. Subsequently, on April 12, 1861, a Confederate attack on Fort Sumter inspired the North to enthusiastically rally behind the Union in a declaration of war.

As the leader of the moderate faction of the Republican Party, Lincoln confronted Radical Republicans, who demanded harsher treatment of the South, War Democrats, who called for more compromise, anti-war Democrats (called Copperheads), who despised him, and irreconcilable secessionists, who plotted his assassination. Politically, Lincoln fought back by pitting his opponents against each other, by carefully planned political patronage, and by appealing to the American people with his powers of oratory. His Gettysburg Address became an iconic endorsement of the principles of nationalism, republicanism, equal rights, liberty, and democracy.