The Massachusetts Provincial Congress
When The Mass. Government Act of 1774 annulled their charter the people of Massachusetts responded with the Mass. Provincial Congress. The Provincial congress was an extra-legal body formed out of need for communications between towns and for decisions to be made in regard to the colonies' future. With John Hancock as president this completely illegal body operated as the Government of all of Massachusetts outside British controlled Boston. The mere existence of such a congress angered Gage because of it's threat to his authority.
The Congress met in Concord for 4 days to discuss their current situation on April 11. When the British marched to Concord and Lexington many Militia, including Paul Revere believed it was to arrest both Sam Adams and John Hancock.