Abraham Lincoln (February 12, 1809 – April 15, 1865) is the 16th President of the United States, serving from March 1861 until his assassination in April 1865.

Lincoln successfully leads his country through its greatest constitutional, military and moral crisis – the American Civil War – preserving the Union while ending slavery, and promoting economic and financial modernization.

Reared in a poor family on the western frontier, Lincoln is mostly self-educated, and becomes a country lawyer, a Whig Party leader, Illinois state legislator during the 1830s, and a one-term member of the United States House of Representatives during the 1840s.

After a series of debates in 1858 that give national visibility to his opposition to the expansion of slavery, Lincoln loses a Senate race to his arch-rival, Stephen A. Douglas.

Lincoln, a moderate from a swing state, secures the Republican Party nomination.

With almost no support in the South, Lincoln sweeps the North and is elected president in 1860.

His election is the signal for seven southern slave states to declare their secession from the Union and form the Confederacy.

The departure of the Southerners gives Lincoln's party firm control of Congress, but no formula for compromise or reconciliation i found.

Lincoln explains in his second inaugural address: "Both parties deprecated war, but one of them would make war rather than let the Nation survive, and the other would accept war rather than let it perish, and the war came."

When the North enthusiastically rallies behind the national flag after the Confederate attack on Fort Sumter on April 12, 1861, Lincoln concentrates on the military and political dimensions of the war effort.

His goal is now to reunify the nation.

As the South is in a state of insurrection, Lincoln exercises his authority to suspend habeas corpus, arresting and temporarily detaining thousands of suspected secessionists without their trials.

Lincoln prevents British recognition of the Confederacy by skillfully handling the Trent affair in late 1861.

His efforts toward the abolition of slavery include issuing his Emancipation Proclamation in 1863, encouraging the border states to outlaw slavery, and helping push through Congress the Thirteenth Amendment to the United States Constitution, which finally frees all the black slaves nationwide in December 1865.

Lincoln closely supervises the war effort, especially the selection of top generals, including commanding general Ulysses S. Grant.

Lincoln brings leaders of the major factions of his party into his cabinet and pressures them to cooperate.

Under Lincoln's leadership, the Union sets up a naval blockade that shuts down the South's normal trade, takes control of the border slave states at the start of the war, gains control of communications with gunboats on the southern river systems, and tries repeatedly to capture the Confederate capital at Richmond, Virginia.

Each time a general fails, Lincoln substitutes another until finally Grant succeeds in 1865.

An exceptionally astute politician deeply involved with power issues in each state, Lincoln reaches out to War Democrats and manages his own reelection in the 1864 presidential election.

As the leader of the moderate faction of the Republican party, Lincoln finds his policies and personality are "blasted from all sides": Radical Republicans demand harsher treatment of the South, War Democrats desire more compromise, Copperheads despise him, and irreconcilable secessionists plot is death.

Politically, Lincoln fights back with patronage, by pitting his opponents against each other, and by appealing to the American people with his powers of oratory.

His Gettysburg Address of 1863 becomes the most quoted speech in American history.

It is an iconic statement of America's dedication to the principles of nationalism, republicanism, equal rights, liberty, and democracy.

At the close of the war, Lincoln holds a moderate view of Reconstruction, seeking to reunite the nation speedily through a policy of generous reconciliation in the face of lingering and bitter divisiveness.

Six days after the surrender of Confederate commanding general Robert E. Lee, however, Lincoln is assassinated by actor and Confederate sympathizer John Wilkes Booth.

Lincoln's death is the first assassination of a U.S. president and sends the nation into mourning.

Lincoln has been consistently ranked by scholars and the public as one of the three greatest U.S. presidents, the others being George Washington and Franklin D. Roosevelt.