As a lead-in to the planned stories in our Newsletter by Mike Green on American Units and uniforms during the Revolutionary War, a description of the Departments of the Continental Army may be useful.
Generally, there were seven territorial departments, although their boundaries were subject to change and they were not all in existence throughout the war.
Canadian Department
The establishment of the Department of New York in an 1776, reflected the aspirations of the Continental Congress and some Americans to annex the British province of Quebec. The Americans had captured Montreal in November 1775 although the region was never entirely under the control of the Continental Army. After the Invasion of Canada failed, all troops were withdrawn to Fort Ticonderga, New York. The Canadian Department was officially discontinued on July 8, 1776.
Eastern Department
The Eastern Department was formed around those states that had originally sent troops to support the Siege of Boston. This was essentially the New England department, and included the states of New Hampshire, Massachusetts (including the present state of Maine), Rhode Island, and Connecticut. For the first year of the war, the field army associated with this department, under the command of General Washington, was variously designated as the Continental Army, Grand Army, or Main Army. The Eastern Department was formally established on April 4, 1776 when the Main Army under moved from Boston to New York City. The department was discontinued in November 1779.
Northern Department
The predecessor of the Northern Department was the New York Department, which was established on June 25, 1775. This department was sometimes described as the Separate Department and the troops stationed in it were known as the Separate Army.
The original New York Department's boundaries were extended to include Canada but was established as a separate department on January 17, 1776. When the Middle Department was created on February 27,1776 the New York Department was merged into it. The Middle Department, as originally organized, included all of the colonies of New York, New Jersy, Pennsylanvia, Delaware, and Maryland. The Northern Department was formally established from the Middle Department on April 14, 1776. The reorganized Northern Department included only that portion of the colony of New York north of the Hudson Highlands, and the present state of Vermont. The field army associated with the Northern Department was known as the Northern Army. The department was discontinued upon the death of its last commander, General Alexander, at Albany on January 15, 1783.
Highlands Department
The Highlands Department was the smallest in area. Strictly speaking, it was part of the Middle Department, but because of its importance it was virtually a separate department. The Highlands Department was formed around the defenses on the Hudson River about 50 miles north of New York City. After the British occupied New York City in 1776 the defenses just north of there became critically important. The presence of British naval forces at New York emphasized the importance of the Hudson River, and both sides in the war recognized the importance of controlling that waterway. The Americans created fortifications, including West Point with its chain across the river. Washington assigned Continental troops to the Highlands on November 12,1776 and there was a Continental Army garrison in the Highlands from then until the end of the war. One of the most notable incidents in the history of this department was the defection of Benedict Arnold in September 1780.
Middle Department
The Middle Department was established on February 27, 1776. Originally it included all of the colonies of New York, New Jersey, Pennsylvania, Delaware, and Maryland. In April 1776, the Main Army moved from Boston to New York, and became the field army associated with the Middle Department for the remainder of the war. A portion of New York north of the Hudson Highlands, and the present state of Vermont were separated from the Middle Department and organized as the Northern Department. The Middle Department then comprised the Hudson Highlands in the state of New York, the rest of New York south of the Highlands, and the states of New Jersey, Pennsylvania, Delaware, and Maryland.
Some of the Continental Army's most important campaigns were fought in this department. These included the New York, the New Jersy Philadelphia, and Monmouth campaigns. It included the battles of Trenton and Princeton. It included winter quarters at Valley Forge. After the Monmouth Campaign, on June 28, 1778, major military operations in the United States shifted to the Southern Department. The department existed until the close of the war. It was the scene of one of the war's last episodes when the British Army evacuated New York City on November 25, 1783.
Western Department
The Western Department covered the frontier territories west and northwest of Virginia and Pennsylvania, including the present states of Ohio, Indiana, Illinois, Michigan, and Wisconsin. It extended from :Pittsburg to the illnois country and as far north as the southern peninsula of Michigan. The department was established in 1777. George Rogers Clark's Illinois campaign of 1779 was one of the most notable operations in this department. This department was the only one to remain after the war and was kept for guarding the western frontier outposts.
Southern Department
The Southern Department was formally established on February 27, 1776. The department included Virginia, North Carolina, South Carolina, and Georgia and the western frontiers of those colonies, from which were created the present states of West Virginia, Kentucky, Tennessee, Alabama, and Mississippi. The field army associated with this department was known as the Southern Army. The Southern Department was the most independent of the commands due to geography and the need for year-round operations. Most of the territorial departments to the north of this department suspended offensive operations for the winter and early spring. This department was the location of the Siege of Yorktown, in 1781, which effectively decided the outcome of the war. The Southern Department existed until the close of the war.