Which 1777 Revolutionary War campaign brought crucial French aid to the American cause?

The Saratoga campaign brought crucial French aid to the American cause.

The campaign took place in 1777 as British forces attempted to control the Hudson River valley and divide New England from the other colonies. British general John Burgoyne advanced south from Quebec, but American resistance, difficult terrain, and growing supply problems weakened his army.

After battles at places including Bennington and Saratoga, Burgoyne surrendered his army to American general Horatio Gates on October 17, 1777. The surrender demonstrated that the Continental forces could defeat a major British army. It also persuaded France that the American rebellion had a realistic chance of success.

France formally allied with the United States in 1778 and supplied troops, money, weapons, and naval support. French assistance became especially important later at Yorktown. Saratoga is therefore often described as a turning point, although the war continued for several more years before the Treaty of Paris ended it.