Few wartime battles are more renowned than that of Bunker Hill. The skirmish is well known to Bostonians as an exemplification of perseverance and tenacity, helping the American colonies free themselves from the yolk of Great Britain during the Revolutionary War, despite facing tremendous adversity and overpowering numbers on the opposite side. The Battle of Bunker Hill took place on this day in Boston history in 1775, exactly 239 years ago. Happy Bunker Hill Day, everybody.

There are a few tidbits you might already know about the bloody Battle of Bunker Hill, like that it actually took place on nearby Breed’s Hill, that an American revolutionary dropped the famous line “don’t fire ’til you see the whites of their eyes,” and that we technically lost.

But there’s a reason this fight in particular is celebrated as a legal Massachusetts holiday in Suffolk County. It proved to be a pivotal, albeit early, indicator in the war that the Americans wouldn’t succumb to British rule.

Here’s how it went down.

After the British marched on Lexington and Concord months prior and were subsequently repelled, they began the Siege of Boston in which they would eventually barricade Boston Harbor and isolate the city from the rest of the country. During this time, though, American forces had set up siege lines of their own, surrounding the British in Charlestown all the way down to Roxbury.

The British then attempted to fortify many of Boston’s and the surrounding area’s hills, because of the tactical advantage of occupying higher ground. Learning of the British threat to the hills of Charlestown, militiamen began fortifying Breed’s Hill in the middle of the night. According to the Massachusetts Historical Society, approximately 1,000 untrained fighters began setting up shop on Breed’s Hill to the astonishment of the British.

In fact, British generals woke up the next morning completely unaware that any such measures had been taking place. With ships anchored offshore in Boston Harbor, the British started firing upon the militia hoping to deter their defensive efforts. Taking their sweet time, some 2,000 British soldiers commenced their march on the hill hours after it had been fortified.

Breed’s Hill at this point was absolute Hell. The British cannonading ignited sweeping flames and razed nearby homes to the ground. Troops were held off by the militia in part due to their various security measures as well as their sheer bravery. A second charge proved equally unsuccessful and, as noted by the Mass. Historical Society, “again the colonists slaughter the King’s troops with their fire.”

Reinforced by 400 men and supplied with ample ammunition, the British staged a third attempt on the hill, at which point Colonel William Prescott, whose likeness now keeps watch over the commemorative obelisk on Breed’s Hill in Boston, was unable to sustain defenses. Running low on supplies, Prescott decided to abandon the hill to the British.

Though the colonists would lose the hill and the battle, it’s generally regarded as an American victory because of the substantial casualties incurred by the opposition. According to the Smithsonian, the number of British who were either killed or wounded was 1,054. For the colonists, that number hovered just over 400, including the notorious death of General Joseph Warren, a leading patriot who now lies in Forest Hills Cemetery in Jamaica Plain.

So while you’re celebrating this monumental day in history, one that helped shape the very fabric of our nation, raise one or two (10) for those who fought and died in the creation of the land of the free.

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