The Rottweiler is one of the oldest of herding breeds. With a history possibly dating back to the Roman Empire, the Rottweiler may be a descendant of ancient Roman drover dogs; a mastiff-type dog that was a dependable, rugged dog with great intelligence and guarding instincts. During their quest to conquer Europe, the Roman legions traveled in large numbers across the continent. The lack of refrigeration meant soldiers brought herds of cattle for food. Drover dogs kept the herd together and guarded it at night. Around A.D. 74 the Roman army travelled across the Alps and into what is now southern Germany. For the next two centuries the Roman drover dogs were continually used in herding and driving cattle for trade even after the Romans were driven out of the area by the Swabians.
A town in this region was eventually given the name Rottweil. It became an important trade center and the descendants of the Roman cattle dogs proved their worth by driving the cattle to market and protecting the cattle from robbers and wild animals. The dogs are said to have been used by traveling butchers at markets during the Middle Ages to guard money pouches tied around their necks. The dogs were eventually known as Rottweiler Metzgerhunds, or "butcher dogs". As railroads became the primary method for moving stock to market, the demand for the Rottweiler breed declined, as did their numbers, so severely diminished by 1882 that a show in Heilbronn, featured only one very poor representative of the breed.
The buildup to World War I saw a great demand for police dogs, which led to a revival of interest in the Rottweiler. During the First and Second World Wars, Rottweilers saw service in various roles, including as messenger, ambulance, draught, and guard dogs. The Deutscher Rottweiler-Klub (DRK, German Rottweiler Club), the first Rottweiler club in Germany, was founded on 13 January 1914, and followed by the creation of the Süddeutscher Rottweiler-Klub (SDRK, South German Rottweiler Club) on 27 April 1915 and eventually became the IRK (International Rottweiler Club). The DRK counted around 500 Rottweilers, and the SDRK 3000 Rottweilers. The goals of the two clubs were different. The DRK aimed to produce working dogs and did not emphasise the morphology of the Rottweiler.
The various German Rottweiler Clubs amalgamated to form the Allgemeiner Deutscher Rottweiler Klub (ADRK, General German Rottweiler Club) in 1921. This was officially recorded in the register of clubs and associations at the district court of Stuttgart on 27 January 1924. The ADRK is recognised worldwide as the home club of the Rottweiler. In 1931 the Rottweiler was officially recognised by the American Kennel Club. In 1936, Rottweilers were exhibited in Britain at Crufts. In 1966, a separate register was opened for the breed. In fact, in the mid-1990s, the popularity of the Rottweiler reached an all-time high with it being the most registered dog by the American Kennel Club. In 2013, the American Kennel Club ranked the Rottweiler as the ninth-most popular pure-breed in the United States.