Fortification of Dorchester Heights - Geography and Strategy

Geography and Strategy

The British military leadership, headed by General William Howe, had long been aware of the importance of the Dorchester Heights, which, along with the heights of Charlestown, had commanding views of Boston and its outer harbor. The harbor was vital to the British, as the Royal Navy, at first under Admiral Samuel Graves, and later under Admiral Molyneux Shuldham, provided protection for the troops in Boston, as well as transportation of supplies to the besieged city. Early in the siege, the British planned to seize both of these heights, beginning with those in Dorchester, which had a better view of the harbor than the Charlestown hills. It was the leaking of this plan that precipitated events leading to the Battle of Bunker Hill.

When Washington took command of the siege in July 1775, he considered taking the unoccupied Dorchester Heights, but rejected the idea, feeling the army was not ready to deal with the likely British attack on the position. The subject of an attempt on the heights was again discussed in early February 1776, but the local Council of Safety believed the British troop strength too high, and important military supplies like gunpowder too low, to warrant action at that time. By the end of February, Knox had arrived with the cannon from Ticonderoga, as had additional supplies of powder and shells. Washington decided the time was right to act.