By 1775, the British Prime Minister, Lord North, had had enough. He and Parliament had made conciliatory gestures to the troublesome North American colonies twice already. The first by repealing the Stamp Act in 1766 and the second by repealing the Townsend Acts in 1770. He was not going to do the same with the Coercive Acts. In February 1775, Parliament and King George III declared the Massachusetts Colony in a State of Rebellion.
In April 1775, General Thomas Gage, the Governor General of Massachusetts and commander of the occupying army in Boston, correctly believed that the radical patriot group Sons of Liberty were behind most of the overt acts of rebellion and the nucleus of the shadow government, the Massachusetts Provincial Council, which controlled most of the colony outside of Boston. The council was raising rebel “minuteman companies” of militia (because they said they were ready to fight at a minute’s notice) to oppose the British.
On of 17 April 1775, Gage received intelligence that two of the Sons of Liberty’s most important leaders, Sam Adams and John Hancock, were in Lexington, 12 miles away. Also, there were cannon, gunpowder and muskets for the minuteman companies located further up the road at Concord. As he had several times before, Gage organized a column of troops to go and seize the stores from the rebels. But this time, he had the chance to seize the leadership of the Sons of Liberty. Every regiment he commanded wanted to take part in the raid. So he assembled the light and grenadier companies from the ten different regiments in his army. The next day, he received permission to seize the rebels and their stores.
At 9 pm on 18 April 1775, Dr. Joseph Warren informed two of the few remaining Sons of Liberty in Boston, William Dawes and Paul Revere, of the raid. Dr. Warren told them to watch the Old North Church and if they saw one lantern in steeple, the British raiding force was moving via the Boston Neck; if there were two lanterns, they moved by boat across the Charles River estuary. Revere and Dawes would then alert the countryside of the British Army’s movements and raise the minuteman companies.
At 10 pm, the 700 troops under Lieut. Col. Francis Smith and his executive officer, Major John Pitcairn, loaded barges off of the Boston Commons. Dr. Warren immediately had two lanterns placed in Old North Church, and Revere and Dawes departed for Lexington, rousing minute companies along the way. The British landed at Lechmere Point at 11pm and began their march on Lexington and Concord.