In July 1862, George B. McClellan’s Peninsula Campaign ended and Union forces slowly began their trek back from Virginia’s backwaters, stunned by their losses. But if it was a failure on the battlefield, as a logistical operation, it was a stunning success, one of the great organizational feats of human history, all thanks to one man: Quartermaster General Montgomery C. Meigs.

The huge operation involved the movement of over 100,000 uniformed troops from Washington by over 400 ships; 600,000 complete rations to start with and 2.5 million more following the army’s arrival; a daily flow of three pounds of provisions per soldier per day, and 25 pounds per horse per day – over 500 tons in all each day that had to be brought down to carry out McClellan’s bold operation. The machinery to make this all happen essentially had to be built from scratch. Stepping into a hierarchy bereft of even a semblance of organization or preparedness, Meigs fashioned a brutally efficient military structure that rooted out rampant graft and fed, clothed and housed an army of then-unimagined size – and would continue to do so for the duration of the war. Perhaps the Union would have won anyway, but it is hard to imagine victory without Meigs’s war machine.

Library of CongressQuartermaster General Montgomery C. Meigs

It’s impossible to overstate the logistical challenges facing the Union Army at the start of the Civil War. The expansion of the Army from around 16,000 men in 1860 to half a million just two years later created a nightmare of supply, which was both nonexistent and uncontemplated before cessation. The new army would need uniforms – many, given the rigors of marching – as well as food, blankets for the cold, good tents to withstand the elements, hospitals at the front and horses and mules as well as the provender to keep them functional. Above all, it required transportation via railroad and wagon not just to move soldiers to the front, but a constant, daily supply of all these imperatives together, something made especially difficult by shifting supply lines, rebel cavalry and movement into enemy territory where the Union did not enjoy convenient interior lines.

Many in the North expected a quick conflict, and the Union was initially not ready to sustain any long engagement, which is precisely what it had on its hands after the First Battle of Bull Run. There was no effective system in place to support an Army of the size that would be necessary to put down the rebellion. Into this void in 1861 stepped Meigs, who in just one year set in place the mechanisms to feed and run the Union war machine to victory.

Montgomery Meigs had an impressive life story well before the war began. He was born into a prominent Philadelphia family in 1816 whose roots in America could be traced back to nearly 1630 and whose members played an active part in the Revolutionary War. His grandfather had been the president of the University of Georgia and his father was a highly respected physician.

He attended the University of Pennsylvania before entering West Point, where he graduated near the top of his class in 1836 in a group that included eight other Civil War generals. He was then assigned to the Corp of Engineers, the military’s most prestigious branch, while other contemporaries like Ulysses S. Grant (infantry), William T. Sherman (artillery) and Jefferson Davis (infantry) were placed in less-desired slots. Over the next 15 years, Meigs would at various times work closely alongside other men who would play crucial roles in the war, including Robert E. Lee, P.G.T. Beauregard, Henry W. Halleck and William Rosecrans.

For the first few years after graduation, Meigs worked around Philadelphia on harbor improvements along the Delaware River, but in 1841 he was shipping to the northern frontier at Detroit to help build the nation’s defenses to head off a possible British invasion from Canada. He would spend nearly the next decade helping construct Fort Wayne in Michigan and Fort Montgomery along Lake Champlain, between northern Vermont and New York. The invasion never came, and as a result Meigs missed out on the Mexican-American War.

In 1852, Meigs was called back east to Washington, where he was soon given a series of assignments that would hold enormous significance in the capital’s history. The first was the building of an aqueduct for the needy city. Washington in 1850 was not a sight to behold. A city of approximately 40,000 (a quarter of whom were slaves), the capital was a stagnant dump, made up of mostly ramshackle housing. The streets were unpaved and often unnavigable, with refuse tossed everywhere and animals shambling about. Crime was largely unchecked. Commenting on its primitiveness, Henry Adams wrote, “No one seemed to miss the comforts of civilization.” The air quality was bad, but the water was worse; filthy at the canal around the Potomac and Eastern Branch, there was no central water supply for the city’s people to drink bath or bathe in, or with which to fight fires.

Placed in charge of the water project, Meigs surveyed the area around the capital, ultimately recommending an aqueduct to Great Falls, Va. He was given control of the project by Secretary of War Jefferson Davis, with whom Meigs would work closely over the next few years. It was through Meigs’s planning and supervision that Washington took a critical step toward modern civilization and an eventual water supply.

Meigs was also tasked as supervising engineer of the Capitol extension. Like the rest of the city, the building was ill equipped to serve the government. It had awful ventilation and became frigid in winter and stifling in summer, and in the chamber its acoustics could make it all but impossible for members to hear one another. More broadly, the Capitol lacked the grandeur befitting of the ambitious nation. Meigs jumped headfirst into the project, involving himself with every detail. He built close relationships with members of Congress and helped increase its funding as well as its interior design, personally hiring the Italian artist Constantino Brumidi, who would paint many of the Capitol’s beautiful frescoes.

Notoriously prickly, Meigs clashed with both the architect Thomas U. Walter and the Buchanan administration’s secretary of war, John Floyd, who ultimately banished Meigs until the start of the war, when President Lincoln brought him back to help organize the defense of Fort Pickens, Fla. Lincoln then placed him at the head of the quartermaster’s office, in charge of supplying the entire Army.

Meigs immediately faced immense challenges. In 1861, the Army was a befuddling mess whose lack of overarching structure bred choking inefficiency. Alongside the battlefield commands sat seven bureau heads – the adjunct general, commissary general, surgeon general, paymaster general, chief engineer, chief of ordnance and quartermaster general – who reported not to the general in chief, but instead to the secretary of war, causing perpetual friction between general staff officers and the civilian secretary. Furthermore, the lack of an organized hierarchy gave the bureau heads license to do as they pleased, particularly under a weak hand like Lincoln’s first secretary of war, Simon Cameron.

Meigs was just one of many chiefs, but his bureau took up approximately a quarter of the Army’s budget of $176 million in fiscal year 1862. The first year of the war was difficult for the entire Union effort, and Meigs was no exception, as he began to grapple with these problems of organization, supply, fraud and inefficiency. All supply demands filtered up through countless middlemen from regiment to brigade to division to corps to the top, and so requests were often inaccurate or inflated, putting a strain on Meigs’s ability to coordinate their delivery. Because of tight budgeting from Congress early in the war, Meigs’s staff was small, and he had pitifully few inspectors in the field to investigate and uncover fraud.

Scrupulously ethical, Meigs took his duties of providing honest estimates and requests for his budget seriously, and he immediately created an auditing system to identify abuses. Early in the war, Meigs was instrumental in exposing the rampant fraud in General John C. Frémont’s Western Department and helping push the general from his post. With equal doggedness, Meigs rooted out incompetent administrators, who were rife in a system built on political patronage, and replaced them with men selected on merit.

By midsummer 1862, Meigs had also built up clothing stores capable of supplying the half-million man Army, as well as the flow of new recruits. When Lincoln made a new call for recruits in July, Meigs was prepared, and began publishing ads for new contracts for his department.

He was also willing to rethink convention. Take tents: the best ones were made with cotton, and Meigs recognized a plain inability to provide enough material to offer cover for the rain and cold elements to all soldiers. Instead, he began erecting more barracks for the coming winter while trying to rely less on linen tents, which were more porous.

Meigs was excellent, too, in procuring the horses, whether they be to move men, artillery, cavalry forces or supplies. Initially, the Union faced a deepening problem of using too many sickly or aged animals, with contractors selling the Army poor creatures and many inspectors being ill trained to recognize them. Meigs pushed new regulations and training to sharpen inspections, and was therefore better able to provide better capacity: in fiscal year 1862, the Army acquired nearly 110,000 horses and 84,000 mules – not to mention the forage and grain necessary to feed them.

The war would be a long slog until 1865. But unlike the Confederate Army, which habitually suffered from shortages, the Union Army was generally well clothed and better equipped to endure difficult conditions than their Southern counterparts. The wealth of supply and coordination was attributable to Montgomery Meigs’s unsung administrative genius.

Montgomery C Meigs