Lee's Invasion of the North. In May 1863, Robert E. Lee's Confederate Army of Northern Virginia had scored a smashing victory over the Army of the Potomac of Chancellorville.
The essence of open range was the free grazing of cattle on millions of unfenced acres of public land. It was possible to become wealthy raising cattle without owning any acreage. Although most ranchers owned a base operation, some owned millions of acres. America's open range started with the Civil War [1861-1865].