While the number of men who died in the Civil War is estimated at around 640,00, more than twice that number, or a million and a half horses and mules, died during the same period. And while it cost the Federal the equivalent of $475,000 to outfit a regiment, the bill for horses alone nearly broke treasury.
Monument to the 1.5 million horses and mules that died during the Civil War erected outside the Virginia History Society in Richmond.
In September 1861 the Army of the Potomac needed 40,000 horses for cavalry and transportation purposes. At an average cost of $120, or $2800 by today's standards, it was six times as expensive to purchase a horse as opposed to equipping one soldier. By the summer of 1862 the cost to the government had risen by $30 per horse, with an average of 1500 horses a week being supplied to George McClellan's huge army, and that, of course, wasn't even factoring in the costs of feeding.
The demand for horses grew so great that it led to a shortage throughout the north and forays were made into Canada for the purchase of large herds. That shortage not only drove the price up to $175 per horse, or the equivalent of $4100 per, but the seemingly insatiable need for horses became a matter of angst for Quartermaster General Montgomery Meigs. During the first three quarters of 1864, the cavalry alone drew 500 horses a day just to keep even with the number being lost to service.
Perceiving that misuse and abuse of their mounts by the cavalry was the primary cause, Meigs tore off this angry letter to Major General William S. Rosecrans of the Army of the Cumberland:
Compel your cavalry officers to see that their horses are properly groomed. Put them in some place where they can get forage near the railroad or send them to your rear for grass and ear corn. When in good order start them 1,000 at a time, for the rebel communications, with orders never to move off a walk unless they see enemy before or between them; to travel only so far in a day as not to fatigue their horse; never to camp in the place in which sunset finds them; and to rest in a good pasture during the heat of the day. [Also] to keep some of their eyes open night and day, and never to pass a bridge without burning it, a horse without stealing or shooting it, a guerilla without capturing him, or a negro without explaining the President's proclamation.
Operate on their communications. Strike every detached post. Rely more upon infantry than upon cavalry, which in the whole war has not decided the fate of a single battle rising above a skirmish, which taxes the Treasury and exhausts the resouces of the country, and of which we now have afoot a larger nominal strength than any nation on earth. We have over 125 regiments of cavalry, and they have killed ten times as many horses for us as for the enemy.