John Buchanan Floyd (June 1, 1806 – August 26, 1863), was a Virginia politician (legislator and governor), U.S. Secretary of War, and the Confederate general in the American Civil War who lost the crucial Battle of Fort Donelson.

Early Life
Floyd was born at "Smithfield" estate, Blacksburg, Virginia. He was the son of John Floyd (1783–1837), who served as a representative in Congress from 1817 to 1829 and Governor of Virginia from 1830 to 1834.

After graduating from South Carolina College in 1826 (by some accounts 1829), Floyd practiced law in his native state and at Helena, Arkansas, where he lost a large fortune and his health in a cotton-planting venture. In 1839, he returned to Virginia and settled in Washington County, which he represented in the state legislature in 1847–1849 and again in 1853. From 1849 to 1852, he was Governor of Virginia. As Governor, he recommended to the legislature the enactment of a law laying an import tax on the products of states that refused to surrender fugitive slaves owned by Virginia masters.

In March 1857, he became Secretary of War in the cabinet of President James Buchanan, where his lack of administrative ability was soon apparent. In December 1860, on ascertaining that Floyd had honored heavy drafts made by government contractors in anticipation of their earnings, the president requested his resignation. Several days later Floyd was indicted for malversation in office, but the indictment was overruled on technical grounds. There is no proof that he profited by these irregular transactions; in fact, he went out of the office financially embarrassed.

Although he had openly opposed secession before the election of Abraham Lincoln, his conduct after the election, especially after his breach with Buchanan, fell under suspicion, and he was accused of having sent large stores of government arms to Southern arsenals in anticipation of the Civil War.

In the last days of his term, he apparently had such an intention, but, during the year 1860, the Southern States actually received less than their full quota of arms. His resignation as Secretary of War, on December 29, 1860, was precipitated by the refusal of Buchanan to order Major Robert Anderson to abandon Fort Sumter, which eventually led to the start of the war. On January 27, 1861, he was indicted by the District of Columbia grand jury for conspiracy and fraud. John B. Floyd appeared in Washington D.C. on March 7, 1861 to appear in criminal court to answer the charges against him. According to Harper's Weekly March 30, 1861 the indictments were thrown out "THE INDICTMENTS AGAINST FLOYD QUASHED The indictments against Ex-Secretary Floyd have been quashed in the Court at Washington, on the ground—first, that there was no evidence of fraud on his part; and second, that the charge of malfeasance in the matter of the Indian bonds was precluded from trial by the act of 1857, which forbids a prosecution when the party implicated has testified before a Committee of Congress touching the matter."

Civil War
After the secession of Virginia, Floyd was commissioned a major general in the Provisional Army of Virginia, but on May 23, 1861, he was appointed a brigadier general in the Confederate States Army. He was first employed in some unsuccessful operations in the Kanawha Valley of western Virginia under Robert E. Lee, where he was wounded in the arm at the Battle of Carnifex Ferry on September 10. In January 1862, he was dispatched to the Western Theater to report to General Albert Sidney Johnston and was given command of Fort Donelson.

Fort Donelson protected the crucial Cumberland River and, indirectly, the manufacturing city of Nashville and Confederate control of Middle Tennessee. It was the companion to Fort Henry on the nearby Tennessee River, which, on February 6, 1862, was captured by Union Army Brig. Gen. Ulysses S. Grant and river gunboats. Floyd was not an appropriate choice to defend such a vital point, having political influence, but virtually no military experience. General Johnston had other experienced, more senior, generals (P.G.T. Beauregard and William J. Hardee) available and made a serious error in selecting Floyd. Floyd had little military influence on the Battle of Fort Donelson itself, deferring to his more experienced subordinates, Brig. Gens. Gideon J. Pillow and Simon Bolivar Buckner. As the Union forces surrounded the fort and the town of Dover, the Confederates launched an assault on February 15 in an attempt to open an escape route. Although successful at first, indecision on General Pillow's part left the Confederates in their trenches, facing growing reinforcements for Grant.

Early in the morning of February 16, at a council of war, the generals decided to surrender their army. Floyd, concerned that he would be arrested for treason if captured by the North, turned his command over to Gideon Pillow, who immediately turned it over to Buckner. Pillow escaped on a small boat across the Cumberland and the next morning Floyd escaped by steamboat with two regiments from his old Virginia command, just before Buckner surrendered to Grant, one of the great strategic defeats of the Civil War. Floyd was relieved of his command by Confederate President Jefferson Davis, without a court of inquiry, on March 11, 1862. He resumed his commission as a major general of Virginia Militia, but his health soon failed and he died a year later at Abingdon, Virginia, where he is buried in Sinking Spring Cemetery.