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[Detail] An accurate map of North America.

Historical Issue-Analysis and Decision-Making: The Siege of Boston, 1775-1776

Military strategy represents a series of historical decisions made, often with quite obvious consequences. Soon after the Battle of Bunker Hill, George Washington, recently appointed as Commander of the Continental Army, arrived in Boston. He immediately began siege operations against the British. Washington's siege operations were successful in forcing the British Army to evacuate Boston. The map to the left shows the location of the British and American troops in Boston. As usual, the detail of this map, viewed with MrSID, is arresting.

Examine the map and detail above. Then read the following letters written by George Washington in 1775 and 1776.

George Washington to John A. Washington, July 27, 1775, with Map of Boston

"I found a mixed multitude of People here, under very little discipline, order, or Government. I found the enemy in possession of a place called Bunker's Hill, on Charles Town Neck, strongly Intrenched, and Fortifying themselves; I found part of our Army on two Hills, (called Winter and Prospect Hills) about a Mile and a quarter from the enemy on Bunker's Hill, in a very insecure state; I found another part of the Army at this Village; and a third part at Roxbury, guarding the Entrance in and out of Boston. My whole time, since I came here, has been Imployed in throwing up Lines of Defence at these three several places; to secure, in the first Instance, our own Troops from any attempts of the Enemy; and, in the next, to cut off all Communication between their troops and the Country; For to do this, and to prevent them from penetrating into the Country with Fire and Sword, and to harass them if they do, is all that is expected of me; and if effected, must totally overthrow the designs of Administration, as the whole Force of Great Britain in the Town and Harbour of Boston can answer no other end, than to sink her under the disgrace and weight of the expense. Their Force, including Marines, Tories, &c., are computed, from the best accounts I can get, at about 12,000 Men27; ours, including Sick absent, &c., at about 16,000; but then we have a Cemi Circle of Eight or Nine Miles, to guard to every part of which we are obliged to be equally attentive; whilst they, situated as it were in the Center of the Cemicircle, can bend their whole Force (having the entire command of the Water), against any one part of it with equal facility; This renders our Situation not very agreeable, though necessary; however, by incessant labour (Sundays not excepted), we are in a much better posture of defence than when I first came. The Inclosed, though rough, will give you some small Idea of the Situation of Boston, and Bay on this side; as also of the Post they have Taken in Charles Town Neck, Bunker's Hill, and our Posts."

From the "George Washington Papers at the Library of Congress, 1741-1799"

George Washington to Landon Carter, March 25, 1776

"I shall therefore pass them over, and inform you, that having received a small supply of Powder (very inadequate to our wants) I resolved to take possession of Dorchester point, laying East of Boston, looking directly into it, and commanding absolutely the Enemy's Lines on the Neck. To effect this (which I knew would force the Enemy to an engagement or make the Town too hot for them) it was necessary, in the first instance, to possess two heights [editor's note: those mentioned in General Burgoyne's Letter to Lord Stanley in his account of the Battle on Bunker's Hill] which had the entire command of this point the Ground being froze upwards of two feet deep and as impenetrable as a Rock, nothing could be attempted with Earth. We were obliged therefore to provide an amazing quantity of Chandeliers, Fascines &c. for the Work, and on the Night of the 4th., after a severe, and heavy Cannonade and bombardment of the Town, the three preceding Nights, to divert the Enemy's attention from our real object, we carried them on under cover of darkness and took full possession of those heights without the loss of a single Man. Upon their discovering of it next Morning, great preparations were made for attacking us; but not being ready before the afternoon, and the Weather getting very tempestuous much Blood was saved, and a very important blow (to one side or the other) prevented. That this remarkable interposition of Providence is for some wise purpose, I have no doubt; but as the principal design of the manoeuvre was to draw the Enemy to an engagement under disadvantages; as a premeditated Plan was laid for this purpose, and seemed to be succeeding to my utmost wish, and as no Men seemed better disposed to make the appeal than ours did upon that occasion, I can scarce forbear lamenting the disappointment. However, the Enemy, thinking (as we have since learnt) that we had got too formidably posted before the second Morning to be much hurt by them, and apprehending great annoyance from our Works, resolved upon a precipitate Retreat, and accordingly embarked in as much hurry, and as much confusion as ever Troops did, the 17th. Instant, not having got their Transports half fitted, and leaving King's property in Boston, to the Amount, as is supposed, of Thirty, or £40,000 in Provisions, Stores, &c. &c. Many pieces of Cannon, some Mortars, and a number of Shot, Shells, &c. &c. are also left; Their Baggage Waggons, Artillery Carts, &c. which they have been eighteen Months and more preparing, were destroyed; thrown into the Docks, and found drifted on every Shore. In short, Dunbar's destruction of Stores after General Braddock's Defeat, was but a faint resemblance of what we found here."

From the "George Washington Papers at the Library of Congress, 1741-1799"

Think about the map and the letters as you answer the questions below:

  • How did the geography of Boston and its harbor influence the decisions made by General Washington, on one side, and by British General Thomas Gage on the other?
  • What do Washington's letters tell you about his decisions regarding the siege of Boston?
  • Read some of Washington's July 1775 orders to the army or reports to the Continental Congress (find them in the American Memory Timeline segment on "Creating a Continental Army." How does the map help you interpret the documents?
  • How do the documents help you make more sense of the map?
  • Using information from all of the sources, write a paragraph about the decisions facing General Washington when he took command of the Continental Army in Boston in 1775.