Editing Union army (section)

===Subsistence Department===
The mission of the Subsistence Department was the purchase, storage and distribution of [[Foods of the American Civil War|rations]] and related items in a timely manner. It was the smallest of the four supply departments, and even as the army grew to encompass over a million soldiers the department itself barely expanded in size.  Yet it was able to meet its mission to such an extent that President Lincoln once remarked to an officer "Your department we scarcely hear of; it is like a well-regulated stomach, works so smoothly we are not conscious of having it."<ref name="Newell111">Newell & Shrader, pages 109–111</ref>

The authorized strength of the department at the war's start was a Commissary General of Subsistence (CGS) with the rank of colonel, an assistant CGS with the rank of lieutenant colonel, and ten commissaries of subsistence (CS), two with the rank of major and the rest captains. Those not assigned to work at the office of the CGS in Washington were in charge of one of the subsistence depots or purchasing offices, or assigned to the staff of one of the military departments. Although there were no enlisted personnel in the department (all commissary positions at the regimental level being fulfilled by members of the regiment), a small civilian staff of clerks and laborers was assigned to the department.<ref name="Newell111"/>

To meet the needs of feeding the rapidly-expanding Union army, Congress authorized a CS with the rank of captain to be assigned to each brigade in July 1861, and in August 1861 the department was expanded with twelve additional officers, four majors and eight captains. A year later when army corps were officially created a CS with the rank of lieutenant colonel was authorized to serve on their staff, and in February 1863 the department was further expanded when the CGS was promoted to brigadier general, a second assistant CGS was added with the rank of colonel, and two additional majors were authorized.  Eventually in March 1865 Congress formally recognized wartime requirements by authorizing a chief CS with the rank of colonel for each field army, military department and division, and principle subsistence depot; an assistant CS with the rank of colonel assigned to Washington; up to six CS with the rank of lieutenant colonel to serve as inspectors or special duty assignment; a chief CS with the rank of lieutenant colonel for each army corps; and a CS with the rank of major for each division.<ref name="Newell111"/>

The need to fill CS positions among the field units primarily came from volunteer officers or regular officers detailed to the duty, and by the end of the war there were 535 commissaries of subsistence of volunteers, bringing the total complement of officers in the department to 564.<ref name="Newell111"/> Although educating them in the principles of their duty was a constant problem, it was a minor one eventually fixed with time and experience, and those who could not meet the standards of the department were relieved of duty.<ref name="Newell118"/>

During the war the principle subsistence depots and purchasing offices were located in Baltimore, [[Boston]], Chicago, Cincinnati, Louisville, Philadelphia, St. Louis, San Francisco and Washington, D.C.  Depot commissaries, assisted by civilian clerks and laborers, received purchases in bulk at these locations and repackaged them for shipment to armies in the field.  The actual transportation of rations was handled by the Quartermaster Department, requiring close cooperation between the two.  Major beef depots were also established in Alexandria, Virginia, Louisville and Washington. During the war the department developed a highly effective system of base, advanced, and temporary depots, and mobile beef herds which followed behind Union forces in the field.<ref name="Newell118">Newell & Shrader, pages 112–118</ref><ref name="USAL202"/>

The success of the Subsistence Department in meeting the challenges of the war was noted by Secretary Stanton, who observed in 1865 that no operation conducted by the Union army failed on account of the department being unable to meet its obligations.  In total, the department purchased over $361 million in foodstuff and miscellaneous subsistence items from July 1, 1861, to June 30, 1865.  The vast quantities of items managed by the department included over 504 million pounds of hardtack, 223 million pounds of bacon, 200 million pounds of brown sugar, 106 million pounds of fresh beef, 64 million pounds of roasted coffee and more than 322,000 live beef cattle.<ref name="Newell118"/>

;Leadership
At the Civil War's start, the CGS was [[George Gibson (Commissary General)|George Gibson]]. Gibson, who at eighty-six was the oldest serving officer in the army, had been in this position since the department was first created in April 1818 and as such was responsible for establishing its procurement and distribution methods. When he died on September 29, 1861, he was succeeded by his deputy, [[Joseph Pannell Taylor]]. Taylor oversaw the department's expansion during the most eventful years of its history and served until his death on June 29, 1864.  The senior assistant CGS [[Amos Beebe Eaton]] was promoted to the position upon Taylor's death and served as CGS for the rest of the war.<ref name="Newell111"/>