Northwest Indian War

The first major general in the Regular Army was Arthur St. Clair, who was appointed in 1791 to prosecute the Northwest Indian War. After the disastrous Battle of the Wabash, St. Clair was replaced by Anthony Wayne, who successfully concluded the war in 1795. Wayne died in December 1796 and the grade of major general was abolished three months later.^[34]

Quasi-War

After sixteen months in abeyance, the grade of major general was revived in 1798 when the Regular Army was expanded during the Quasi-War with France. As part of the buildup, Congress authorized a lieutenant general, two major generals, and an inspector general and a quartermaster general with the rank of major general. Only one of the two line major general slots was ultimately filled; the other was declined by Henry Knox, who refused to be outranked by the designated inspector general, Alexander Hamilton, who had been junior to Knox in the Continental Army during the American Revolutionary War. The President was also authorized to temporarily augment the Regular Army with a Provisional Army, but it was never fully organized. When tensions eased, the Provisional Army was disbanded and the maximum Regular Army rank was again reduced to brigadier general.^[35]

War of 1812

The grade of major general was revived permanently when the military establishment expanded in anticipation of the War of 1812. The first two major generals were Revolutionary War veterans Henry Dearborn and Thomas Pinckney. After a year of defeats, Dearborn was relieved and four more major generals were appointed: James Wilkinson, Wade Hampton, Morgan Lewis, and William Henry Harrison. A year later, all four had been court-martialled, sidelined, or driven to resign, and George Izard, Jacob J. Brown, and Andrew Jackson were promoted in their place.^[36]

After the war, the number of major generals was reduced to two, Brown and Jackson. In 1821 Congress eliminated the second major generalcy and Jackson departed the Army to become governor of Florida, leaving Brown to become the first Commanding General of the Army.^[37] When Brown died in 1828, the Army's two brigadier generals, Winfield Scott and Edmund P. Gaines, waged such a bitter public campaign for the vacant major generalcy that the President passed them both over in favor of Alexander Macomb. Macomb died in 1841 and was succeeded by Scott.^[38]

Mexican War

Scott remained the Army's senior officer during the Mexican War. After the outbreak of hostilities in 1846, Congress temporarily authorized a second major general on the condition that he be immediately discharged upon the ratification of a peace treaty, and the Army's three brigadier generals were passed over in favor of Zachary Taylor, victor at Palo Alto and Resaca de la Palma. Two more major generals were authorized the following year on the same basis, Gideon J. Pillow and John A. Quitman. After the war, the extra major generals were duly discharged and Scott again became the Army's only major general. Scott was breveted lieutenant general in 1855 but continued to occupy the substantive grade of major general until he retired in 1861.^[39]

Civil War

During the American Civil War, the bulk of the Union Army was composed of volunteer forces raised by individual states and led by dozens of federally appointed major generals of volunteers. The Regular Army itself was authorized a total of five major generals. Three of the new vacancies were filled immediately by former Regular Army officers George B. McClellan, John C. Frémont, and Henry W. Halleck, while Regular Army brigadier general John E. Wool was promoted for capturing Norfolk, Virginia, during the Peninsular Campaign. Subsequent appointments were reserved as prizes for major generals of volunteers who won decisive battlefield victories: Ulysses S. Grant for Vicksburg, William T. Sherman for Atlanta, George G. Meade for Spotsylvania, Philip H. Sheridan for Cedar Creek, and George H. Thomas for Nashville.^[40]

When the volunteers were disbanded after the war, its Regular Army officers reverted to their permanent grades. Many of the most famous Union Army major generals had been appointed to that rank only in the volunteer service and did not achieve the equivalent grade in the Regular Army until years or decades later, if ever. For example, upon mustering out of the volunteers in 1869, Oliver O. Howard reverted to his permanent Regular Army grade of brigadier general and had to wait until 1886 to again be promoted to major general; while George A. Custer never regained his wartime rank in the Regular Army and died as a lieutenant colonel.^[41] Of the dozens of major generals of volunteers who lost their temporary ranks after the Civil War, only nine ever attained the permanent grade of major general in the Regular Army before they retired.^[42]

Postwar

After the Civil War, promotions in the Regular Army virtually ceased due to the reduction in the size of the Army and the youth of its remaining officers. The postwar Army had only three major generalcies, which initially were held by officers whose rapid wartime promotions had advanced them to high command at such a young age that they could occupy the coveted grade for decades, obstructing further promotions. For example, John M. Schofield held his major generalcy for nearly 26 years, and Winfield S. Hancock for nearly twenty.^[43]

To unblock the promotion flow, Congress mandated in 1882 that officers must retire at age 64, but could retire sooner if they had at least forty years of service. Because officers nearing the age limit could now conveniently select their exit dates to coincide with vacancies in higher grades, it became common to fill each vacancy with a parade of aging veterans who would each be promoted and immediately retired with the higher rank and retired pay, as a reward for past service. In January 1904, for example, a single vacant major generalcy hosted five officers in five days, each of the first four in turn being promoted and then retired after only one day in grade to clear the way for the next. Congress blocked this practice in 1906 by requiring that general officers serve at least one year before being allowed to retire at that rank, except for age or disability.^[44]

Major generals of the staff

Officers in the Regular Army were classified either as line officers, who commanded combat formations, or staff officers, who performed specialized support functions. Permanent promotions to general officer grades were only available in the line. Staff officers could temporarily acquire the rank and pay of a general officer while detailed to certain offices designated by statute to carry that rank, such as chief of a staff bureau, but reverted to their permanent grades upon leaving such an office. Officers holding the permanent personal grade of general officer were called general officers of the line, while general officers holding only temporary ex-officio rank were called general officers of the staff.^[4][45]

For most of the 19th century, general officers of the staff were limited to the rank of brigadier general, but in 1900 the rank of the Adjutant General was temporarily increased to major general for the term of its then-incumbent, Henry C. Corbin.^[46] In 1904 Corbin transferred to a line command but retained the office of Adjutant General and its associated rank. In his absence, the Adjutant General's Department was merged with the Record and Pension Office into a consolidated bureau headed by Fred C. Ainsworth, who was appointed Military Secretary with the rank of major general.^[47] The Military Secretary was retitled Adjutant General after Corbin retired in 1906, and the office's rank reverted to brigadier general when Ainsworth was dismissed in 1912.^[48]

Major generals of the staff proliferated after 1912, when the Quartermaster Corps was created under a Quartermaster General bearing the temporary rank of major general. The Surgeon General reached that rank in 1915 when William C. Gorgas was appointed to that post and promoted to major general in the Medical Department to reward his service during the construction of the Panama Canal. The Chief of Coast Artillery became a major general of the staff in 1916. Finally, every other chief of a staff corps, department, or bureau was elevated to major general on October 6, 1917.^[49]

World War I

When the United States entered World War I in April 1917, the President was authorized to raise a temporary force of volunteers and conscripts, initially dubbed the National Army and later referred to as the non-permanent establishment of the United States Army after the Regular Army, National Army, and federalized National Guard were unified on August 7, 1918.^[8] Congress also granted authority to add an appropriate number of general officers to each organization "for the period of the existing emergency," which at first was used only for temporary appointments to major general and brigadier general in the National Army, but was later construed to allow emergency appointments to general and lieutenant general in the Regular Army.^[50] In July 1918 an emergency major general was authorized for service abroad as Assistant Surgeon General with the American Expeditionary Force; Merritte W. Ireland was appointed, followed by Robert E. Noble when Ireland became Surgeon General later that year.^[5] In contrast to the temporary general officers of the National Army or unified United States Army, emergency general officers were considered part of the permanent establishment.^[3] All emergency and temporary commissions expired with the wartime legislation on June 30, 1920.^[2]

After the war the Army was reorganized and the new peacetime establishment was authorized 21 major generals of the line, more than doubling the previous number, plus 13 major generals of the staff, including the newly created Chiefs of Infantry, Cavalry, and Field Artillery. The reorganization took effect on July 1, 1920.^[2]