When the South broke away from the Union, they took all the forts in their borders. Only four were left for the Union. The most important was Fort Sumter. In January of 1861, James Buchanan attempted to send troops to the fort but when the Charleston Harbor batteries fired at the ship, they turned back. In Lincoln's first day in office, he realized that he could not afford to lose Sumter. He also did not want to start war.
In April, he came up with an answer. He would send a supply ship, but, should it be attacked, it would return.
Major Robert Anderson of Fort Sumter surrendered the fort to General P. G. T. Beauregard, the commanding officer of the Confederate troops at Charleston. He did this after defending the fort for one and a half days.

The First battle of Bull Run was started on July 21. The Battle was won by the south after the stand of General Thomas Jackson who was later called "Stonewall"

On November 7, Flag Officer Samuel du Pont, a Union naval commander, took 17 ships, wooden cruisers, to Port Royal Sound off the coast of South Carolina. His guns shot at the batteries on the shore for hours, and they eventually fled. The Union took the bases with 12,000 of General Thomas Sherman.