The main leaders of the Federalist were: Alexander Hamilton
John Jay
John Adams
John Marshall
Rufus King
They did it because King George lll hoped to placate Native Americans who had sided against him during the recently concluded Seven Years' War.
The French and Indian War began in 1754 and ended with the Treaty of Paris in 1763. The war provided Great Britain enormous territorial gains in North America, but disputes over subsequent frontier policy and paying the wars expenses led to colonial discontent, and ultimately to the American Revolution.