Short answers, pulled from the story.
President Abraham Lincoln issued a Proclamation of Blockade on the 19th of April 1861. The document declared that an insurrection had broken out in South Carolina, Georgia, Alabama, Florida, Mississippi, Louisiana, and Texas.
At the start of the conflict, the Union Navy possessed only 42 ships in active service. By war's end, the Union Navy had grown to 671 ships, making it the largest navy in the world.
Blockade runners operated out of Bermuda, the Bahamas, or Havana in Spanish Cuba. They carried compact, high-value cargo like cotton outbound and rifles, medicine, brandy, lingerie, and coffee inbound.
Cotton exports fell 95%, dropping from 10 million bales before the war to just 500,000 bales during the blockade period. This shortage led Egypt to replace the South as Britain's principal source of cotton.
The Battle of Mobile Bay took place on the 5th of August 1864. This engagement closed the last major Confederate port in the Gulf of Mexico.