Thus at the beginning the Southern troops had an advantage. This was peculiarly obvious when the cavalry of the two sections met each other in battle. The Southern horsemen had been "rough riders" from infancy. Many of the Northern men of that arm of the service had never ridden at all except perhaps by way of conducting a gentle and docile farm horse to a watering trough. In the matter of horses, too, the Southerners, and especially the Virginians, had a distinct advantage. Ever since the first settlement of Virginia it had been the custom of men in that nearly roadless state to go everywhere upon horseback. They had consequently given special attention to the breeding of horses fit for strenuous work under the saddle, while in the North horse-breeding had been conducted mainly with a view to harness use. The wiry Virginian thoroughbreds, or half-breds, were far fitter for cavalry service, far more enduring, far quicker of action, far more alert and responsive than the Conestogas or Percherons or handsome and fast trotting Morgans of Pennsylvania, from which state came the first cavalry regiments encountered by Stuart and his born and bred cavaliers, mounted as they were upon "Red Eye" colts or "Revenue" fillies. The Southern troops also had the advantage of fighting defensively in their own country to whose climate they were inured and to the diseases of which they were in the main immune. But apart from these small differences the two armies that confronted each other on the Potomac were composed of substantially the same materials. Later in the war the large enlistment of immigrants gave to the Union army an element that did not at any time exist in the armies of the South. But at the outset there was no important difference. Each army was made up of American youths, full of patriotic fervor, brave, heroic upon occasion, but utterly untrained in the profession of arms. On the Northern side in the early contests of the war there was the advantage of small bodies of regulars, trained to obey orders at all hazards and to stand firm in every moment of danger. These regulars proved themselves of inestimable value in the early actions of the war; but their numbers were so small that their service scarcely counts in the historical reckoning.