British troops finally took the hill after three assaults, but at a staggering cost: over 1,000 casualties against roughly 450 American losses. The battle, fought mostly on Breed's Hill rather than Bunker Hill itself, shattered any illusion of an easy war and gave the fledgling rebellion its first taste of hard-won pride.
General William Howe led his redcoats up the slope in tight ranks, expecting the colonial militia to break and run as they had at Lexington. Instead, dug into hastily built earthworks, the Americans held their fire until the British were nearly on top of them—the origin of the (likely apocryphal but enduring) order 'don't fire until you see the whites of their eyes.'
Two British charges were repulsed with murderous volleys. On the third assault, American ammunition ran out, and the militia finally withdrew, yielding the hill. But the price Howe paid was brutal: nearly half his attacking force fell dead or wounded, including a horrifying number of officers picked off deliberately by colonial marksmen.
Among the dead was Dr. Joseph Warren, a beloved Patriot leader who chose to fight as a common soldier rather than claim rank. News of the battle convinced the Continental Congress, meeting in Philadelphia, that this was now a real war requiring a real army—and within days it formally adopted the Continental Army under a Virginian named George Washington.