“King Cotton” was a slogan used by the Confederacy claiming that cotton exports would make an independent confederate state economically fortunate, ruin the textile industry of New England and most importantly, it would force Great Britain and France to support the Confederacy in the Civil War because their industrial economy depended on cotton textiles. To show their power of King Cotton, southern cotton merchants immediately refused to ship out their cotton to northern textile mills in early 1861. By the summer of 1861, the Union Blockade shut down over 95% of exports.
http://www.youtube.com/watch?v=STw-_DMWm8I