There are 11 : Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, Texas and Virginia.
Abraham Lincoln was elected into office on November 6, 1860, and would not be inaugurated until March 4, 1861. South Carolina didn't like it. By December 20, 1860, South Carolina would be the first of 13 states that seceded from the Union as a key precursor to the Civil War that began on April 12, 1861.
At the dawn of a new year and new presidency, Mississippi held a convention in Jackson. In an 84 to 15 vote, the delegates voted to secede, annulling and abrogating their oaths to the Constitution of the United States. Mississippi in its first article of succession declared itself a “free, sovereign, and independent State.”
Florida became the third of the 13 states that seceded and did so one day after Mississippi. The Florida vote was held in Tallahassee, with secession favored in a 62 to 7 vote. Florida annulled "all political connection" with the United States, and the United States government.
At this point in time, just prior to the Lincoln inauguration, the southern states appeared to be falling like dominoes. One day after Florida, the Alabama delegates decided in Montgomery in a 61 to 39 vote that they would also become one of the states that seceded. In their secession act, they declared Abraham Lincoln and his Vice President Hannibal Hamlin “hostile” to the peace and security of the State of Alabama.
Georgia would become one of the states that seceded just over one week later, in a 209 to 89 vote in Milledgeville. In their secession act, Georgia “repealed, rescinded, and abrogated” the United States Constitution.
It was in Baton Rouge on January 26 in a 113-17 vote when Louisiana left the Union. In their declaration, they dissolved their association with the document entitled “The Constitution of the United States of America.”
Texas would become the seventh of the states that seceded, voting on February 1 in Austin in a 166 to 7 vote. Then commander Brigadier General David Twiggs, initially from Georgia, ordered all forces to be given to Texas. He was fired by the United States government on March 1 but would be appointed a Major General of the Provisional Army of the Confederacy. The “Confederacy” is what the states that seceded were now calling themselves.
A Civil War was now five days old. Fort Sumter had surrendered. An insurrection had been declared by the President of the United States. States in the South that were still part of the Union did not want to answer the call of President Lincoln to end the insurrection. Virginia became the eighth of 13 states that seceded in an 89 to 55 vote. In their secession act, the people of Virginia declared that the Constitution of the United States was “no longer binding” on any citizen of the State.
President Lincoln was now in war-room mode and would block every Southern port. In a 69 to 1 vote in Little Rock, Arkansas became the ninth state that seceded. Alabama declared that “her citizens” were absolved from all allegiances to the United States government.
In a unanimous vote on May 20, North Carolina was thought to be the last of the states that seceded. The Deep South was no longer obliged to the United States Constitution. Three more states would follow. They were all states that had originally rejected a vote to secede.
Tennessee had initially rejected a secession vote in February of the year but would become the eleventh of 13 states that seceded in a 66 to 25 vote in June.