The Battle of Cowpens was an engagement between Patriot forces under Brigadier General Daniel Morgan and British forces under Sir Banastre Tarleton fought on January 17, 1781. As part of the campaign in the Carolinas, a force of 1,100 British under Tarleton were sent against 2000 men under Morgan. The Patriot forces were able to perform a double envelopment of Tarleton’s force, at the cost of only 12 killed and 61 wounded. Tarleton was one of around 160 British troops to escape.
Revisionist historians say that, but contemporary and 19th century accounts suggest the American force was about half that size. He reported to Greene that he had 800, but probably picked up another few hundred irregulars by the time of the battle.
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http://www.mountvernon.org/digital-encyclopedia/article/battle-of-cowpens/