The Battle of Bunker Hill took place on June 17th, 1775. With the outbreak of the war after the Battle of Lexington and Concord, the British commander, Thomas Gage found himself blocked by the Patriots. They occupied the hills to the west of the city. Gage resolved to capture the Charlestown peninsula across the harbor. However, before he could act, on the night of June 16th 1775, around 1,500 American troops of the Massachusetts regiment and Putnam's Connecticut regiment occupied Breed and Bunker Hill on the peninsula. The American troops built a fort on Breed's Hill. The fort was complete by the morning after working all night. The presence of the Americans on the peninsula caused the British ships to open fire on them. The British planned to attack the Americans and drive them away from Bunker Hill. Major General Howe, one of the three generals sent from Britain to assist Gage, was in charge of the operation.
While the British were preparing for the attack, the Americans extended their settlement to the seashore. This was done to prevent a flank attack. More American troops gathered on Bunker but no one wanted the forward positions on Breed's Hill. General William Howe arrived with his force on the southern shore of the peninsula and directed the light infantry to attack the Americans at the seashore. The British dismissed the American troops' ability to resist frontal attacks and overestimated their own troops' ability to make one. The light infantry returned with many casualties. In retaliation, General Howe launched a frontal assault on the American fort. This attack was again driven back by the American troops, despite their shortage of ammunition.
The second attack was launched along the length of the American settlements. The troops retreated with heavy losses. The final attack was made, focused on the center of the American settlement. The American troops lacked ammunition and this final attack drove them off the peninsula. They were not pursued by the British. The British suffered an estimate of 1,150 soldiers killed and wounded. The American casualties were estimated at 450 killed and wounded. Afterwards, the British took over Bunker and Breed's Hill and fortified them, staying there until they evacuated Boston at the end of the year. This battle served as a lesson to the Continental army on what had to be done to build an effective army. All the soldiers fought bravely, but the intended reinforcement refused to advance to support their comrades and this created confusion among the officers.