In May, 1717, we find him reporting upon the Indian situation to Paul Methuen, the then English Secretary of State, that though the English had carefully kept the terms of Lord Howard's Treaty of 1685, the Iroquois "had committed divers hostilitys on our ffrontiers, in 1713 they rob-d our Indian Traders of a considerable cargo of Goods, the same year they murdered a Gent'n of Acco't near his out Plantations; they carried away some slaves belonging to our Inhabitants, and now threaten not only to destroy our Tributary Indians but the English also in their neighbourhood." He adds that such conduct requires "some Reparation" and asks the Secretary to instruct the Governor of New York to cause his Iroquois to "forebear hostilitys on the King's subjects of the neighbouring Colonies and likewise any nation of Indians under their protection."[7]
Neither by temperament nor training was Spotswood a man to acquiesce in such conditions. After consulting with and urging co-operation upon the Governors of Maryland and Pennsylvania, he set out in the winter of 1717-'18 for New York "to demand something more substantial than the bare promises of the Chief men of those Indians, w'ch they are always very liberal of, in expectation of presents from the English, while at the same time their young men are committing their usual depredations upon ye Frontiers of these Southern Governments." He was fortunate in arriving in New York "very opportunely to prevent the march of a Great Body of those Indians w'ch I had Advice on the Road was intended chiefly against the Tributaries of this Governm't, and the Governor of New York's Messengers overtook them upon their march and obtained their promise to Abstain from any hostilitys on the English Governments."
It being late in the season for a conference with the Sachems of the Long House and the New York Assembly being in the "height of its business and like to make a larger session than ordinary," Spotswood arranged, through the Governor of New York, preliminary negotiations with the Indians and returned to his Virginia.
The discussions thus begun dragged along during the ensuing five years. At length, in 1721, the Iroquois sent their representatives to Williamsburg with more definite proposals and in May, 1722, the General Assembly passed an act reciting in detail the terms on which the treaty would be made.[8] Later in the summer Spotswood, with certain of his Council, went to New York on a man-of-war and thence proceeding to Albany (where he was joined by the Governor of Pennsylvania) the new treaty was closed after the usual endless speech making and other ceremony. By its terms the Iroquois were prohibited from ever again crossing the Potomac or the Blue Ridge "without the license or passport of the Governor or commander-in-chief of the province of New York, for the time being"; and the Virginia tributary Indians were similarly prohibited from crossing the same boundaries. Moreover, there were provisions that should any Indians—Iroquois or tributary—ignore the prohibition, they were, upon capture and conviction, to be punishable by death or transportation to the West Indies, there to be sold as slaves. There was added a clause rewarding him who captured an Indian found in Virginia without permission, with 1,000 pounds of tobacco when the latter should be condemned to death; or, if he should be condemned to transportation, the captor should "have the benefit of selling and disposing of the said Indian, and have and receive to his own use, the money arising from such sale."
There was nothing ambiguous in this treaty's terms; the Iroquois in signing it realized that their Piedmont hunting grounds were lost to them and that the sportive raids of their war parties below the Potomac were ended.
And now Spotswood's consulship had reached its end. His enemies in London and Williamsburg had been industriously intriguing and upon his return he found he had been superseded. He had acquired a vast estate of over 45,000 acres in the Piedmont forests and to settle and improve those lands he proceeded to devote his great and able energies. But he had far from retired from his public labours. As Postmaster General for the American Colonies he, by 1738, developed a regular mail service from New England to the James; and was about to sail as a major-general on Admiral Vernon's expeditions against Carthagena when he suddenly died. He was buried on his estate, Temple Farm, near Yorktown, where latterly he had made his home. It was in his mansion there, then owned by his eldest daughter Ann Catherine and her husband M. Bernard Moore, Senior, that many years later the negotiations for the surrender of Lord Cornwallis to General Washington closed the American Revolution.