Driving the British from Boston had required months of grueling work on the part of colonists in New York and Massachusetts Bay. In November of 1775, Washington had dispatched Bostonian Henry Knox to retrieve badly needed cannon from Fort Ticonderoga, New York. Teamsters with eighty yoke of oxen made the three hundred mile journey, bringing 59 cannon for the colonial army then encircling Boston. Once they neared the city, the rebels faced a new challenge. How would they roll the guns into place without tipping their hand to the British? On the night of March 4, 1776, colonial militia and local volunteers stealthily fortified the summit of Dorchester Heights.
Wrapping their wagon wheels with straw to deaden the sound, they moved the cannon from Roxbury and entrenched them on these hills south of Boston. British General Howe planned an attack, but a violent storm prevented his soldiers from landing. Within a few days, Howe, his troops, and a thousand colonial loyalists set sail for Nova Scotia, abandoning the city to Washington's forces and its jubilant citizens. The army improved the fortifications and again stationed troops on Dorchester Heights during the War of 1812. After 1814, however, the twin hills declined in military importance.
Since Boston had annexed Dorchester Neck in 1804, developers eyed the Heights as a source of raw material for the expanding city. During the second half of the nineteenth century the hills of South Boston underwent the same excavation that lowered Mount Vernon and Pemberton and Beacon Hills, the "tri-mountains" of the Boston peninsula. In 1898, the General Court of Massachusetts commissioned a monument to stand on the remaining hill of the Heights. Designed by the architectural firm of Peabody and Stearns, the white marble Georgian revival tower commemorates the 1776 victory. In 1966 the Heritage Conservation and Recreation Service added Dorchester Heights to the National Register of Historic Places. Twelve years later the National Parks and Recreation Act authorized the City of Boston to transfer the site to the National Park Service. At that time, it joined the eight other sites which comprise Boston National Historical Park, established in 1974.
Dorchester Heights adds a valuable dimension to the Park. Its historical significance and the development of the surrounding community vividly reflect the history and growth of the city of Boston. With the fortification of its summit in 1776, Dorchester Heights contributed significantly to one of Boston's major victories and demonstrated the integral connection between the Boston peninsula and her neighboring community. The annexation of Dorchester Neck to Boston in 1804 strengthened that link. Building and landfilling operations cemented the tie by facilitating travel between the two areas.