Why was the American victory at Battle of Sara-toga significant?

How did the Emancipation Proclamation affect the United States economically? Why is industrial wastes are neutralized before releasing in to water? A way the US has not expanded its territory? Which choice most closely means the same as costly? Where did Stephen Douglas and john bell get most of there support? What is allowed with IAW AR 25 2? How did the Communists affect Chinese literature? Who is more powerful Anubis or horos? What is Charles Drew's eye color? What game can you play with your elderly grandmother who is 93 years old and hard of hearing? What were baseball player Orlando Cepeda's total batting stats for 1972? What was the primary reason for slave trade and the plantation system? How do you play byzantine empire in total war? Who discovered the Compound Microscope? What alphabet do the Yemen's use? Greater love hath no man than this that a man lay down his life for his friends? How do rotation and tilt affect the amount of solar energy that different parts of earth receive? Why was the general strategy behind Philip Sheridan's Shenandoah Valley campaign and William Sherman's March to the Sea? How long was duke of Normandy ruling England? Was the bill of rights set up to limit power of the government and protect the rights of individuals?

Why was the American victory at Battle of Sara-toga significant?