Junius, won him favour at court, in spite of occasional flashes of independence, and he was made colonel-commandant of the 16th light dragoons in 1763, governor of Fort William in Scotland in 1768, and major-general in 1772, when his income from these military appointments amounted to 3,500l. a year, on the strength of which he spent considerably more.
In September 1774 Burgoyne was sent out to America to reinforce General Gage. It was with the utmost reluctance that Burgoyne consented to leave his invalid wife (see his curious private memorandum on his appointment in Fonblanque's Political and Military Episodes, 120-35). He arrived at Boston in May 1775, and at once heard the news of the skirmish at Lexington. From the moment of his arrival Burgoyne was chafed by his forced inaction, and he bitterly complains that, owing to the number of generals and brigadiers, he had nothing to do. He occupied himself in a correspondence with the American general Lee, who had served with him in Portugal, and in writing home letters of bitter complaint. He witnessed the battle of Bunker's Hill, and returned home in disgust in November 1775. It was then determined to attack the colonists at once in the south, in New England, and in Canada. Burgoyne was attached to Sir Guy Carleton, the commander-in-chief in Canada, as second in command. He reached Canada in June 1776, the very month in which Lady Charlotte Burgoyne died, and found Carleton in command of 12,000 men. With him Burgoyne advanced, and, after a naval battle with a newly built flotilla on Lake Champlain, occupied Crown Point and reconnoitred Ticonderoga. Disgusted at Carleton's inaction, Burgoyne returned home, and at the request of the prime minister drew up a plan of campaign for the next year. He proposed that an army of 12,000 men, accompanied by 2,000 Canadians as guides and pioneers, and 1,000 Indians as scouts, should advance from Canada, take Ticonderoga, and then advance for two hundred miles through the forests to Albany in the state of New York, where a junction should be formed with a division from the army of Sir William Howe. His energy impressed the king and the ministry, and he returned to America in the spring of 1777 with supreme command of a force to make this march. On his arrival he soon found that his army would not consist of the 12,000 soldiers he had expected, and he eventually started, after issuing a bombastic proclamation, with only 6,400 soldiers and 649 Indians, from the Three Rivers in May 1777. The army was far too small, and not well found in stores and ammunition; but it was full of enthusiasm, and he was well supported by his officers. His advance was at first successful, and after reoccupying Crown Point he took Ticonderoga on 6 July, after six days' siege. The king wished to confer the order of the Bath on Burgoyne; and when Lord Derby refused this on his behalf, he insisted on promoting him lieutenant-general on 29 Aug. 1777. Burgoyne slowly moved forward after too much delay. He failed in his attack on a small American force at Bennington, and then crossed the Hudson. But difficulties accumulated; Arnold cut off his retreat, and Schuyler, with 16,000 men, blocked his advance. He was disheartened by the news that the force under Clinton had not stirred; yet he determined to keep on advancing. Schuyler continued to retreat before him, until he was superseded by Gates, who believed the time was come to stand at bay. Accordingly, on 24 Sept., Burgoyne found the American army, of nearly 20,000 men, strongly entrenched on Behmus' Heights, and immediately attacked it, though his own troops were reduced to 5,000 men. The attack was futile, and he had to attempt to retreat. But the American general would not allow him to escape; he harassed every mile of his retreat, and at last surrounded him at Saratoga. All Burgoyne's provisions and ammunition were expended, and he found himself obliged to surrender to Gates on 17 Oct. 1777.
Burgoyne at once obtained leave from General Washington in a most courteous letter (Fonblanque, p. 214) to return to England, and had to face a storm of disapprobation. In the House of Commons he found no friends but Charles James Fox and his immediate supporters, and on 26 May 1778 had to answer a motion by Mr. Vyner, 'to condemn the state and condition of the army which surrendered at Saratoga,' in which he asked why Burgoyne had been allowed to return to England. He defended himself in an able speech, which he afterwards published; but a select committee to examine the state of the army was appointed by a large majority. He had also to meet the anonymous attacks of the public press, and published his 'State of the Expedition from Canada, as laid before the House of Commons by Lieutenant-general Burgoyne and verified by Evidence,' in which he proved that his army was one-half the size he had demanded, and in every way badly provided. The attacks on him continued; and after pretending to order him to return to America as a prisoner of war, which he refused to do,