The British government ordered Sir Guy Carleton, the Governor of Canada, to help mount an offensive operation into New York from Canada. The expedition, commanded by Major-General John Burgoyne, was composed of 4,000 British regulars, 3,000 Brunwick and Hessen-Hanau (German) troops, 105 Canadian militia, and 500 Iroquois.
The British force seized the American fort at Crown Point on 20 June 1777. When Burgoyne's force reached Ticonderoga on 1 July, the American garrison fled to the south. By 13 September, the British army had reached Saratoga, 50 miles (80 kilometres) north of Albany on the Hudson River. There, American Generals Horatio Gates and Benedict Arnold and 12,000 American troops confronted the British.
Fought eighteen days apart in the fall of 1777, the two Battles of Saratoga were a turning point in the American Revolution. The battle began on September 19 began when Burgoyne moved some of his troops in an attempt to flank the entrenched American position on Bemis Heights. Benedict Arnold anticipated the manoeuvre and placed significant forces in his way. Burgoyne did gain control of Freeman's Farm, but it came at the cost of significant casualties.
His gains were erased when he again attacked the Americans in the October 7th Battle of Bemis Heights and the Americans captured a portion of the British defences. Burgoyne was therefore compelled to retreat and his army was surrounded by the much larger American force at Saratoga. Burgoyne pleaded with General Howe for reinforcements, but Howe refused to send any troops from the coast. Meanwhile, additional American troops arrived. Faced with insurmountable odds and no hope of reinforcements, Burgoyne surrendered his army to General Gates on 17 October 1777.
The terms negotiated with the American general were titled the Convention of Saratoga. It specified that the troops would be sent back to Europe after giving a parole that they would not fight again in the conflict. Under guard, they were marched to Cambridge, Massachusetts, where they arrived on 8 November. The rank and file were quartered in crude barracks that had been constructed during the 1775 siege of Boston, while most of the officers were billeted in houses.
News of Burgoyne's surrender was instrumental in formally bringing France into the war as an American ally, although it had previously given supplies, ammunition, and guns, notably the de Valliere cannon which played an important role in Saratoga. This battle also resulted in Spain joining France in the war against Britain.
