American Civil War: Jefferson Davis resigns from the United States Senate.

Jefferson Finis Davis (June 3, 1808 December 6, 1889) was an American politician who served as the president of the Confederate States from 1861 to 1865. As a member of the Democratic Party, he represented Mississippi in the United States Senate and the House of Representatives before the American Civil War. He previously served as the United States Secretary of War from 1853 to 1857 under President Franklin Pierce.

Davis was born in Fairview, Kentucky, to a moderately prosperous farmer, the youngest of ten children. He grew up in Wilkinson County, Mississippi, and also lived in Louisiana. His eldest brother Joseph Emory Davis secured the younger Davis's appointment to the United States Military Academy. After graduating, Jefferson Davis served six years as a lieutenant in the United States Army. He fought in the MexicanAmerican War (18461848), as the colonel of a volunteer regiment. Before the American Civil War, he operated a large cotton plantation in Mississippi, which his brother Joseph gave him, and owned as many as 113 slaves. Although Davis argued against secession in 1858, he believed states had an unquestionable right to leave the Union.

Davis married Sarah Knox Taylor, daughter of general and future President Zachary Taylor, in 1835, when he was 27 years old. They were both stricken with malaria soon thereafter, and Sarah died after three months of marriage. Davis recovered slowly and suffered from recurring bouts of the disease throughout his life. At the age of 36, Davis married again, to 18-year-old Varina Howell, a native of Natchez, Mississippi, who had been educated in Philadelphia and had some family ties in the North. They had six children. Only two survived him, and only one married and had children.

Many historians attribute some of the Confederacy's weaknesses to Davis's poor leadership. His preoccupation with detail, reluctance to delegate responsibility, lack of popular appeal, feuds with powerful state governors and generals, favoritism toward old friends, inability to get along with people who disagreed with him, neglect of civil matters in favor of military ones, and resistance to public opinion all worked against him. Historians agree he was a much less effective war leader than his Union counterpart, President Abraham Lincoln. After Davis was captured in 1865, he was accused of treason and imprisoned at Fort Monroe in Hampton, Virginia. He was never tried and was released after two years. While not disgraced, Davis had been displaced in ex-Confederate affection after the war by his leading general, Robert E. Lee. Davis wrote a memoir entitled The Rise and Fall of the Confederate Government, which he completed in 1881. By the late 1880s, he began to encourage reconciliation, telling Southerners to be loyal to the Union. Ex-Confederates came to appreciate his role in the war, seeing him as a Southern patriot. He became a hero of the Lost Cause of the Confederacy in the post-Reconstruction South.

The American Civil War (April 12, 1861 – May 9, 1865; also known by other names) was a civil war in the United States between the Union (states that remained loyal to the federal union, or "the North") and the Confederacy (states that voted to secede, or "the South"). The central cause of the war was the status of slavery, especially the expansion of slavery into territories acquired as a result of the Louisiana Purchase and the Mexican–American War. On the eve of the Civil War in 1860, four million of the 32 million Americans (~13%) were enslaved black people, almost all in the South.The practice of slavery in the United States was one of the key political issues of the 19th century. Decades of political unrest over slavery led up to the Civil War. Disunion came after Abraham Lincoln won the 1860 United States presidential election on an anti-slavery expansion platform. An initial seven southern slave states declared their secession from the country to form the Confederacy. Confederate forces seized federal forts within territory they claimed. The last-minute Crittenden Compromise tried to avert conflict but failed; both sides prepared for war. Fighting broke out in April 1861 when the Confederate army began the Battle of Fort Sumter in South Carolina, just over a month after the first inauguration of Abraham Lincoln. The Confederacy grew to control at least a majority of territory in eleven states (out of the 34 U.S. states in February 1861), and asserted claims to two more. Both sides raised large volunteer and conscription armies. Four years of intense combat, mostly in the South, ensued.

During 1861–1862 in the war's Western Theater, the Union made significant permanent gains—though in the war's Eastern Theater the conflict was inconclusive. On January 1, 1863, Lincoln issued the Emancipation Proclamation, which made ending slavery a war goal, declaring all persons held as slaves in states in rebellion "forever free." To the west, the Union destroyed the Confederate river navy by the summer of 1862, then much of its western armies, and seized New Orleans. The successful 1863 Union siege of Vicksburg split the Confederacy in two at the Mississippi River. In 1863, Confederate General Robert E. Lee's incursion north ended at the Battle of Gettysburg. Western successes led to General Ulysses S. Grant's command of all Union armies in 1864. Inflicting an ever-tightening naval blockade of Confederate ports, the Union marshaled resources and manpower to attack the Confederacy from all directions. This led to the fall of Atlanta in 1864 to Union General William Tecumseh Sherman and his march to the sea. The last significant battles raged around the ten-month Siege of Petersburg, gateway to the Confederate capital of Richmond.

The Civil War effectively ended on April 9, 1865, when Confederate General Lee surrendered to Union General Grant at the Battle of Appomattox Court House, after Lee had abandoned Petersburg and Richmond. Confederate generals throughout the Confederate army followed suit. The conclusion of the American Civil War lacks a clean end date: land forces continued surrendering until June 23. By the end of the war, much of the South's infrastructure was destroyed, especially its railroads. The Confederacy collapsed, slavery was abolished, and four million enslaved black people were freed. The war-torn nation then entered the Reconstruction era in a partially successful attempt to rebuild the country and grant civil rights to freed slaves.

The Civil War is one of the most studied and written about episodes in the history of the United States. It remains the subject of cultural and historiographical debate. Of particular interest is the persisting myth of the Lost Cause of the Confederacy. The American Civil War was among the earliest to use industrial warfare. Railroads, the telegraph, steamships, the ironclad warship, and mass-produced weapons saw wide use. In total the war left between 620,000 and 750,000 soldiers dead, along with an undetermined number of civilian casualties. President Lincoln was assassinated just five days after Lee's surrender. The Civil War remains the deadliest military conflict in American history. The technology and brutality of the Civil War foreshadowed the coming World Wars.