I just read about this, something I hadn’t heard of. During the American Revolution the 13 colonies formed the Commities of Correspondence to coordinate writings outside the colony. It formed like a political union between the states to help rally support or resistance to issues. It’s a little confusing for me to get a feel for exactly what it was but it says they spread messages on horseback and on ships and they also had members who were part of the secret Sons of Liberty, the underground patriot group who included Patrick Henry, John Adams, Paul Revere, Samuel Adams, and other prominent rebels.
Their first formal meeting was in opposition to the 1764 Currency Act. The committee stayed together for other important actions such as the Stamp Act Congress and the Gaspee Afair, the Tea Act. Hundreds of committees formed throughout the colonies. The First Continental Congress was planned in these Committies. Cool stuff.