This week marks the anniversary of the Battles of Lexington and Concord. Two hundred and forty-four years ago, farmers, tradesmen, laborers, and mariners–Americans of all stripes–came to together to defend themselves against the most professional army in the world.

April 19, 1775 marked the beginning of an epic journey for a band of brothers who risked EVERYTHING for a nation yet to be born. Over the course of nearly eight years, many of these Americans marched thousands of miles, often shoeless, unpaid, and starving, to fight for freedom and liberties most Americans today take for granted. Their resolute stand matters in light of multiple current events and threats to that American liberty.

In November 1774, King George III told Lord North, the Prime Minister of Great Britain that “blows must decide whether they [colonists but hereafter referred to as the Americans] are to be subject to this country, or independent.” The Crown moved toward using force. For years, friction had been building in the provinces. Throughout the fall of 1774, General Gage’s forces conducted a number of so-called powder alarms aimed at seizing gunpowder and munitions. Black powder in the colonies was precious and had to be imported since virtually no organic production existed in North America. The Crown put in place a ban on the importation of powder and firearms.

Mercilessly, they leveled a number of hard economic measures, closed the port of Boston throwing thousands out of work, and passed several acts aimed to destroy the colonies’ economic will. Americans fought back by boycotting British products. In early 1775, after declaring the colonies in a state of rebellion, the Crown ordered General Gage, the commander-in-chief of British forces in North America and military governor of the Province of Massachusetts Bay, to use a “vigorous exertion” of that force and “seize the principal actors and evaders” as well as disarm the Americans. During the previous several months, most colonists had hoped for peace and still considered themselves Englishmen as they prepared to defend themselves. The British had demonstrated throughout the history of their empire that without powder and cannon to support a standing army, any rebellion could be easily crushed. Until reinforcements arrived, however, Gage must conduct the disarmament raids with surgical precision, knowing the colonists could recruit potentially overwhelming forces. He spent weeks preparing for the operation to seize rebel munitions that Americans had amassed at Concord.

The operation to seize the Patriots’ powder and cannon located by Gage’s spies at Concord unfolded around 10:00 p.m., April 18, 1775. Over 700 British regulars under the command of Lieutenant Colonel Francis Smith began their journey toward Lexington and Concord.

The remarkable full story will be captured in my forthcoming book—the successor to my bestselling book, Washington’s Immortals: The Untold Story of an Elite Regiment Who Changed the Course of the Revolution.

Smith detached six companies of his elite light infantry and Marines, led by Major John Pitcairn, to march ahead of the column and secure two bridges that led into Concord. He also wisely sent a messenger to Boston for reinforcements—the corpulent officer knew he would need them.

Pitcairn placed a hard-charging Irish Marine, Lieutenant Jesse Adair, along with a Tory scout at the front of the column. Under Adair’s command, the light infantry marched at double-time ahead of Smith’s main force.

Through the first faint gray streaks of dawn, Adair’s vanguard saw the fields and hills come alive with armed men darting toward Lexington. One officer remembered “a vast number of Country Militia going over the Hill with their arms to Lexington.” The Americans had been alerted by Paul Revere and other riders that Smith’s regulars were on the march.

Rounding a bend in the road, the British saw the darkened silhouettes of Lexington’s meetinghouse and homes.

A drum beat called the Americans to arms. Captain John Parker’s militia assembled on the northeast corner of Lexington Common. A veteran of the French and Indian War, Parker knew how to fight. He was also terminally ill with tuberculosis and only had five months to live, but John Parker would have one more great fight in him. Parker’s militia had been up all night after Revere’s initial warning that the Redcoats were on the march toward Concord. Parker barked to his men:

“Let the troops pass by. Don’t molest them, without they being first.”

One American heard a British officer shout, “Damn them, we will have them!” Parker’s over 70 Patriots nervously eyed the British, as one exclaimed, “There are so few of us, it would be folly to stand here.”

It was. The Americans were outnumbered and outgunned. A game of chicken ensued.

Parker firmly implored his troops, “Stand your ground! Don’t fire unless fired upon! But if they want a war, let it begin here.”

Major Pitcairn rode toward the group and yelled to Parker’s men, “Throw down your Arms, ye Villains, ye Rebels!”

None of Parker’s men laid down their arms. But Parker mysteriously changed his orders to “disperse and not to fire.”

Pitcairn barked, “Surround and disarm them.”

Another American heard a British officer shout, “Ye villains, ye rebels, disperse, damn you, disperse!” The Redcoats shouted “huzza! huzza!” to intimidate the Americans.

Some men slowly dispersed, others stood their ground, but nobody laid down their arms.

Time seemed to stand still.

And then the high-pitched crack of a shot pierced the morning air of the New England common.

Nobody knows which side fired first.

The British charged and fired into Parker’s men only about 30 to 60 yards away.

Although known for their iron discipline, training, and tactical prowess on the battlefield, the British officers had lost control of their men. The troops ran wildly through the green.

In the ensuing chaos, some Americans held their ground, ignoring Parker’s orders to withdraw. Parker’s cousin, Jonas Parker, did not move an inch, although writhing in pain from a gunshot wound. Knocked prone from the force, on his hands and knees, Parker attempted to reload his musket. One of his fellow Americans heard him declare, “[that] he would never run.” Shortly after uttering those words, a Redcoat charged, impaling the New Englander with a bayonet and disemboweling him. Horrified by the unfolding bedlam and his men shooting Americans without orders, Major Pitcairn rode out into the melee and drew his sword flashing it feverishly in the air, signaling a ceasefire. Eight Americans, including several pairs of fathers and sons, would ultimately die during the engagement. Multiple other Americans were wounded.

After regaining control of his men, Smith addressed his officers and only now informed them of their mission: to march to Concord and seize and destroy the cannon and munitions the provincials had secreted away there.

Several of the officers risked their careers and told Smith to abandon the mission. The entire countryside had been alerted. Smith dismissed the warnings and insisted he had his orders. The British column trudged toward Concord. In the distance they heard the drone and toll of Concord’s church bell pressed into service as an alarm. By about 7:30 a.m., the long column of troops that sprawled nearly a quarter of a mile arrived in the town.

To counter the British, militia and minutemen from Concord and surrounding towns, wielding a miscellany of their own personal arms, proudly assembled on the hill behind Concord’s meetinghouse. The leaders of the militia ordered their men not to fire unless fired upon and after a debate decided to withdraw to another hill nearly a mile from the center of Concord near North Bridge that led into the town.

With the center of Concord clear of Americans, Smith ordered his men, without warrants, to search and destroy any munitions or weapons of war located in the town. Following intelligence furnished from Gage’s spies and American traitor Dr. Benjamin Church, they knew exactly where to start looking. After holding a gun to the head of the local tavern owner, they were able to locate several cannons buried behind the tavern, which they disabled. They also found a few wooden gun carriages for artillery and thousands of musket balls that they tossed in a millpond. The British mission of disarmament at Concord had failed. The forewarned Americans had successfully moved most of their stockpiles.

Smith’s troops manhandled the cannon carriages and rolled them into a blazing fire. But soon flames from the inferno spread to the nearby structures.

In a bizarre juxtaposition, the Revolution paused, and both sides put aside their differences. Locals in Concord and the Crown’s troops formed a bucket brigade to extinguish the flames that consumed a nearby structure.

On the hill overlooking Concord’s North Bridge, the minutemen and militia who saw the billowing clouds of white smoke reached a different conclusion.

Seeing the plumes of smoke, young lieutenant Joseph Hosmer stormed over to the militia leaders who debated their next move, “Will you let them burn the town down?!” The senior American Colonel James Barrett who wore, “an old coat, a flapped hat, and a leather apron” and whose farm was now being raided by Smith’s troops, looked at the faces of his men. The men showed no fear and urged Barrett to march on Concord. Barrett ordered hundreds of men forward but warned not to shoot first and wait until fired upon.

In practically a repeat of Lexington—a shot rang out, but this time the British clearly fired first.

The shot was later dubbed “the shot heard round the world” by poet and grandson of Reverend Emerson, Ralph Waldo Emerson.

One British soldier fired without orders, followed by two others, and then the front British ranks erupted in a sheet of flame and smoke as they discharged a volley.

Several provincials fell, and many suffered wounds from the fusillade.

The skirmish continued for several minutes until the Americans forced the British back into the center of Concord where they reformed and eventually marched toward Boston. Shortly after the melee, a rogue American scalped and bashed the skull of a defenseless wounded British soldier with a tomahawk–the savage attack would contribute to fueling additional atrocities in the ensuing battles.

Smith’s walking wounded with bandaged arms, legs, and heads marched alongside the hitherto unscathed. The light infantry fanned out in an attempt to protect the flanks of the Redcoat column. In the distance, the ridges and hills teemed with swarms of men assembling from the towns in the area.

The first mile of march was uneventful until the column hit a juncture known as Meriam’s Corner where several country lanes merged. Here, minutemen and militia ambushed the British. Using the terrain to their advantage, the Americans hid behind boulders, trees, and stone walls while pouring a deadly volley into the retreating redcoats. The light infantry advanced on the flanks sometimes surprising and slaying the colonists who fought from their homes and farms.

Perched on a boulder-strewn hill outside Lexington, John Parker and his men patiently waited to pounce on Smith’s column. Running low on ammunition and having already sustained dozens of casualties, Smith’s men ran into an ambush that history dubbed “Parker’s Revenge.”

Hit by multiple ambushes, exhausted, out of ammunition, and having sustained many dead and wounded, the men neared the ends of their ropes. Most of Smith’s troops felt like only a miracle could save them.

That miracle came in the form of 1,300 troops led by Lord Percy who arrived to rescue the expeditionary force from “inevitable destruction.”

***

Percy formed a marching square several columns wide with the light infantry moving ahead working the flanks. Around 3:15 p.m. after several delays, Percy ordered his men forward, “it began now to grow pretty late, and we had 15 miles to retire, & only 36 rounds.” As the columns and flankers surged forward, British pipers and drummers mockingly played “Yankee Doodle.”

General William Heath, the American commander in charge of the minutemen and militia, countered with a moving envelopment of Percy’s troops which the English nobleman described as “an incessant fire, which like a moving circle surrounded & fol[lowe]d us wherever we went.”

Minutemen and militia, indiscernible during the battle, swarmed the British from all flanks.

The Americans defended their homes firing from windows and doors, “The soldiers were so enraged at suffering from the unseen enemy that they proceeded, and put at death all those found in them,” recalled Frederick Mackenzie an officer in the Royal Welch Fusiliers. Quarter was not always granted, and the British executed several prisoners after they surrendered. Denison Wallis ran for his life after the Redcoats shot the men around him. Wallis had been struck 12 times and left for dead, but lived to tell what he had witnessed. In and around the grounds of Jason Russell’s house a dozen Americans, including its owner, were killed defending the home. Russell, 59 and lame, refused to leave the dwelling, and he reportedly declared, “An Englishman’s house is his castle.” A macabre scene of weltering, bayonet and bullet-riddled bodies of her husband and other Americans greeted Jason Russell’s wife when she returned to her home after the battle. She described the floor of the kitchen as a lake of blood “almost ankle deep.”

The Americans would not yield, and the Redcoats ran into many a man like 78-year-old Captain Samuel Whittemore who protected his home as he hid behind a stone wall killing a soldier and firing his pistol to slay another. While attacking a soldier with his sword, a ball blew off part of his cheekbone. Then the Redcoats bayoneted him numerous times, “shouting we have killed the old rebel.” Whittemore lay in a pool of his own blood having been bayoneted six or eight times, and his hat and clothes “were shot through in many places,” but he would survive and live to be 96.

Burning homes, killing livestock, and plundering anything they could cram in their haversacks, including the church communion silver, the Brits defied Gage’s orders and embarked upon an orgy of violence. They lost more men as they pushed east to break through the American gauntlet. A blood red sun set on the British troops many of whom had not slept for two days, as they finally made their way into Charlestown and set up defensive positions ironically on a place known as Bunker Hill.

In the morning, the British would find Boston surrounded by thousands of Americans. Fearing an attack from within Boston, Gage took the entire town hostage and banned Americans from leaving the city. Next, he implemented a gun register and confiscation scheme. Inhabitants were promised they could leave Boston if they turned in their weapons and registered them with British officials for safe-keeping. Americans turned in over 2,000 pistols and long arms along with nearly 1,000 bayonets. Weeks passed before those who so desired, could leave Boston, and the weapons were never returned. Later, Gage issued a proclamation that anyone who did not lay down their arms would be considered “rebels” and “traitors.” As the British gathered American weapons, the Americans gathered depositions on the Battles of Lexington and Concord from colonialists and even captured British soldiers. Employing a fast ship, they would beat Gage’s slow transport brig carrying his report to Britain by nearly two weeks. The American version of events sparked a sensation in London and British papers. The propaganda war to win hearts and minds had commenced.

Years after the Revolution, Captain Levi Preston was asked why he fought in the Battle of Lexington. Was about the Stamp Act? “I never saw one of those stamps.” Was it about the Tea Tax? “I never drank a drop of that stuff; the boys threw it all overboard.” The interviewer then asked him about several esoteric concepts which Preston dismissed. Americans don’t like to be told what to do. As he then responded, “Young man, what we meant in going for those red-coats was this: we always had governed ourselves, and we always meant to. They didn’t mean we should.”

Patrick K. O’Donnell is a bestselling, critically acclaimed military historian and an expert on elite units. He is the author of 12 books including The Unknowns and Washington’s Immortals which has been named one of the 100 Best American Revolution Books of All Time by the Journal of the American Revolution. O’Donnell served as a combat historian in a Marine rifle platoon during the Battle of Fallujah and speaks often on espionage, special operations, and counterinsurgency. He has provided historical consulting for DreamWorks’ award-winning miniseries Band of Brothers and for documentaries produced by the BBC, the History Channel, and Discovery. PatrickkODonnell.com @combathistorian