These photos show cowboys and dudes as they round up cattle on the Montana Range, 1939

These photos, taken by Farm Security Administration photographer Arthur Rothstein, show cowboys and friends at Quarter Circle U Ranch in Big Horn County, Montana as they gather their herds for the seasonal roundup.

Roundups were conducted within a specific amphitheater area and were not used to move cattle from one point to another. Instead, roundup was the process of gathering and gathering all the cattle that were grazing in that specific area. Roundup was held twice a year, in spring and fall.

Spring Roundup was an opportunity to gather all the calves together to be branded and counted, so a rancher knew exactly how many calves were born that year. In addition to the branding, Cowboys differentiated the market-era steers (known as "beeves") that were sold.

Fall Roundup was used primarily to determine which steers were ready to go out to sell to a meat packing plant.

The time it takes to complete a roundup varies, depending on the area the cowboys have to ride to find all the cattle.

A roundup requires a number of specialized skills on the part of both cowboys and horses. Individuals who separated cattle from the herd required the highest level of skill and rode specially trained "biting" horses, trained to follow the movements of the cattle, compared to other horses. I was able to stop and turn fast.

Once the cattle were sorted, most cowboys had to rope young calves and prevent them from being branded and (in the case of most bull calves) calfed. Sometimes it was also necessary to stop old cattle for branding or other treatment.

A large number of horses were needed for the roundup. Each shepherd would need three to four new horses over the course of a day's work. The horses themselves were also rounded up.

In the West it was common for young cubs to be born from tame mares, but they were allowed to grow "wild" to a semi-wild stage in the open range. There were also "wild" herds, often referred to as Mustangs.

Both types were rounded, and mature animals were tamed, a process known as horse braking, or "broncho-busting", (var. "broncho busting") usually performed by cowboys who were training. Horses are distinctive.

The historic American shepherd of the late 19th century originated from the vaquero traditions of northern Mexico and became a figure of particular importance and legend.

One subtype, called a wrangler, specifically bred horses to work cattle. In addition to farm work, some cowboys work for or participate in rodeos.

The historical role of cowgirls, who were first defined as such in the late 19th century, was less well documented, but in the modern world serve similar functions and receive considerable respect for their achievements.

The cowboy has deep historical roots that go back to the early European settlers in Spain and the Americas. Over the centuries, differences in terrain and climate, and the influence of animal-handling traditions from many cultures, created tools, clothing, and many different styles of animal handling.