The King's Royal Regiment of New York was formed by exiled Loyalist leader, Sir John Johnson, from American refugees, fleeing rebel persecution,[1] the regiment served with distinction throughout the war, launching raids and relief missions into the Mohawk Valley of New York.

The regiment was instrumental in the siege of Fort Stanwix, during the expedition of Colonel Barry St. Leger, down the Mohawk River Valley, in the summer of 1777,[citation needed] and saw action, that same year, in the Saratoga Campaign, at the Battle of Oriskany, Carleton' s Raid, in 1778, and the devastating raid on the Schoharie Valley, in 1780.

This region was a major agricultural area of New York, and these raids were intended to interdict the supply of foodstuffs to General George Washington's army while pressuring the Revolution's political leaders in the region, who were actively persecuting Loyalist residents as traitors aiding and supplying British troops.

Johnson soon left Montreal to chase the retreating Continental Army southwards down the Richelieu Valley towards Lake Champlain.

He met Carleton at Fort Chambly, where the Governor authorized Johnson to raise the King's Royal Regiment of New York.

St. Leger's army included a small force of regular British soldiers, a large American Indian contingent comprising Six Nations and Canadian Indian warriors, a contingent of Hessian soldiers, volunteers under Joseph Brant's command, and the King's Royal Yorkers under Johnson's command.

During the siege, a relief column of 800 men under the command of General Nicholas Herkimer and comprising New York militia advanced towards Fort Stanwix.

(Battle of Klock's Field) New York City remained in British hands until the end of the war, behind the protection of its large garrison and the Royal Navy.

In 1783, the 1st Battalion of the King's Royal Yorkers was disbanded and settled along the St. Lawrence Valley in the vicinity of Cornwall in modern Stormont and Dundas counties.

Sir John Johnson settled in Montreal and also held farms in Williamstown, Ontario and the seigneuries of Monnoir and Argenteuil in Quebec.