"Facing the threat of rebellion, British General Thomas Gage hoped to prevent violence by ordering the seizure of weapons and powder being stored in Concord, Massachusetts, twenty miles northwest of Boston. Departing Boston late in the evening on April 18, 1775, the King’s troops marched into the small town of Lexington at around 5:00 AM. the next morning. Waiting to greet them was a small company of militia commanded by Captain John Parker.
A shot rang out – historians still debate who pulled the trigger. Nervous British soldiers then fired a volley, killing seven militiamen and mortally wounding another. Parker’s men fled, while the British soldiers moved on towards Concord, arriving around 8:00 AM.
By the time the British arrived at the North Bridge, a force of almost 400 colonial militiamen from Concord and the surrounding area had gathered on the high ground across the river. The Minute Men formed up and advanced on the British, who responded by retreating back across the bridge and taking up a defensive position. When the British troops opened fire, the Minute Men responded with a volley of their own, killing three British soldiers and wounding nine others. The British troops fell back to the town."
The British, realizing their vulnerability, decided to return to Boston. Their retreat turned into a rout, however, as thousands of militiamen attacked the British column from all sides. Shooting from behind trees, rocks, and buildings, the Patriots inflicted heavy casualties on the retreating Redcoats.
By the time the fighting stopped, the British had lost 73 men killed and many more wounded, compared to the Patriots’ loss of 49 men killed."
LEXINGTON AND CONCORD: THE SHOT HEARD 'ROUND THE WORLD
https://www.battlefields.org/learn/revolutionary-war/battles/lexington-and-concord