Internal British politics

During this time the British did not present a united front toward the American Patriots. The Parliament of Great Britain at this time was informally divided between conservative (Tory) and liberal (Whig) factions. The Whigs generally favored lenient treatment of the colonists short of independence while the Tories staunchly upheld the rights of Parliament. The Whigs felt that the Tory policies were pushing Americans to rebel, while the Tories thought Whig leniency (such as repealing the Stamp Act) was doing the same. Many Whigs freely associated themselves with the American Patriot cause, which Tories thought were encouraging the Americans in their resistance. The result was that, although Lord North's Tory government usually had a Parliamentary majority, a large Whig minority opposed it and constantly criticized its policies.^[39] Meanwhile, Whig commanders in America such as Sir William Howe and his brother Admiral Howe came under the suspicion of Tories and Loyalists for not vigorously prosecuting the war effort.^[40]

First phase, 1775–1778

Outbreak of the War 1775–1776

Massachusetts

Main article: Boston campaign

In February 1775 Parliament declared Massachusetts to be in a state of rebellion. Lieutenant General Thomas Gage, the British North American commander-in chief, commanded four regiments of British regulars (about 4,000 men) from his headquarters in Boston, but the countryside was in the hands of the Revolutionaries. On April 14, he received orders to disarm the rebels and arrest their leaders.

The British marching to Concord in April 1775

On the night of April 18, 1775, General Gage sent 700 men to seize munitions stored by the colonial militia at Concord, Massachusetts. Riders including Paul Revere alerted the countryside, and when British troops entered Lexington on the morning of April 19, they found 77 Minutemen formed up on the village green. Shots were exchanged, killing several Minutemen. The British moved on to Concord, where a detachment of three companies was engaged and routed at the North Bridge by a force of 500 minutemen. As the British retreated to Boston, thousands of militiamen attacked them along the roads, inflicting many casualties before timely British reinforcements prevented a total disaster. With the Battles of Lexington and Concord, the war had begun.^[41]
The militia converged on Boston, bottling up the British in the city. About 4,500 more British soldiers arrived by sea, and on June 17, 1775, British forces under General William Howe seized the Charlestown peninsula at the Battle of Bunker Hill. The British mounted a costly frontal attack.^[42] The Americans fell back, but British losses totaled over 1,000 men. The siege was not broken, and Gage was soon replaced by Howe as the British commander-in-chief.^[43] General Gage wrote to the Secretary at War in London:

These people show a spirit and conduct against us they never showed against the French….They are now spirited up by a rage and enthusiasm as great as ever people were possessed of and you must proceed in earnest or give the business up. A small body acting in one spot will not avail, you must have large armies making diversions on different sides, to divide their force. The loss we have sustained is greater than we can bear. Small armies cannot afford such losses, especially when the advantage gained tends to do little more than the gaining of a post.^[44]

In July 1775, a newly appointed General Washington arrived outside Boston to take charge of the colonial forces and to organize the Continental Army. Realizing his army's desperate shortage of gunpowder, Washington asked for new sources. Arsenals were raided and some manufacturing was attempted; 90% of the supply (2 million pounds) was imported by the end of 1776, mostly from France.^[45] Patriots in New Hampshire had seized powder, muskets and cannons from Fort William and Mary in Portsmouth Harbor in late 1774.^[46] Some of these munitions were used in the Boston campaign.
The standoff continued throughout the fall and winter. During this time Washington was astounded by the failure of Howe to attack his shrinking, poorly armed force.^[47] In early March 1776, heavy cannons that the Patriots had captured at Fort Ticonderoga were brought to Boston by Colonel Henry Knox, and placed on Dorchester Heights. Since the artillery now overlooked the British positions, Howe's situation was untenable, and the British fled on March 17, 1776, sailing to their naval base at Halifax, Nova Scotia, an event now celebrated in Massachusetts as Evacuation Day. Washington then moved most of the Continental Army to fortify New York City.^[48]