What happened at the Battle of Guilford Courthouse?

The Battle of Guilford Courthouse was a clash between Continental Army and militia under the command of General Nathaniel Greene and the main body of the British Southern Army under General Cornwallis. The battle marked the end point of Cornwallis's extended campaign in the Carolinas that began with the capture of Charleston in 1780. Cornwallis had hoped to secure the Carolinas, which the British knew contained a significant population of Loyalists. At the battle, militia and Continental regulars held their own against a smaller British force before eventually leaving the battlefield to the British. The battle was thus technically a British victory. But Cornwallis's losses were so significant (he lost over 500 men) that he abandoned the campaign in the Carolina backcountry, marching instead into Virginia. The decision would prove to be a fateful one--it was in Virginia that Cornwallis's army was trapped at Yorktown, effectively ending the war. So the battle marked a significant turning point in the war.