Department of the East

The Department of the East was a military administrative district established by the U.S. Army several times in its history. The first was from 1853 to 1861, the second Department of the East, from 1863 to 1873, and the last from 1877 to 1913.

As part of a major reorganization of the Western Territories, after October 31, 1853 the division echelon was eliminated and the six western departments consolidated into four (Departments of Texas, New Mexico, the West, and the Pacific). The four departments (1st-4th) of the Eastern Division were similarly consolidated into the Department of the East, with boundaries encompassing all the states east of the Mississippi River. It remained thus until August 17, 1861, when the American Civil War, created a need for a vast increase in the Union Army and more departments to administer them and the Department of the East was discontinued.

On January 3, 1863, the Department of the East was revived, to administer the many districts and posts created by the Civil War in New York, New Jersey and the states of New England. It became subordinate to the Military Division of the Atlantic, from 1865 to 1866 and the Division of the Atlantic, in 1868 until this department was discontinued in 1873.

Again the Department of the East was revived in 1877, once again subordinate to the Division of the Atlantic, until the Division was discontinued in 1891. In 1911, it became subordinate to a new Eastern Division, until the Department of the East was discontinued 1913, being replaced by the Eastern Department. The Eastern Department was discontinued when the Army's command was reorganized by the 1920 amendment to the 1916 Defense Act.

The headquarters of the 1853–1861 Department of the East in 1861 was Troy, New York.

The headquarters of the last Department of the East was originally located in leased office space in New York City until 1878, when the War Department relocated all headquarters functions across the country to army posts due to economic considerations. The headquarters was relocated to Fort Columbus, renamed Fort Jay in 1904 on Governors Island in New York Harbor.

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