Where does Ellis locate the origins of political parties in the U.S.?

After the Revolution, when the Founding Fathers agreed to join the colonies in a loose government system under the Articles of Confederation, they had no intention of forming political parties.

Yet by 1787, it was clear that the Articles of Confederation were no longer appropriate for the needs of the nation. Therefore, the Constitutional Convention met in Philadelphia to propose a new form of government. George Washington presided over the Convention, and many of the foremost Founding Fathers were in attendance, including: James Madison, Benjamin Franklin, and Alexander Hamilton. Considered the first American political party, the Federalists grew in power after Washington was elected President in 1789. Formed by Alexander Hamilton, the Federalist Party was committed to a nationalist government. They founded the first national bank and reestablished trading opportunities.