The Australian Shepherd, often known simply as the 'Aussie', is a medium-sized breed of dog that was, despite its name, developed on ranches in the United States during the 19th century. There is disagreement regarding the exact history of the breed prior to its arrival in the United States, and thus no official consensus on the origin of its name or association with Australia. These dogs require a minimum of one hour a day of play, exercise, and attention. They need space to run and play in an urban setting. It had to handle severe weather; have plenty of speed, athleticism, energy, and endurance; and be intelligent, flexible, and independent; while remaining obedient. The actual foundation for the Australian Shepherd was established between the 1940s and the early 1970s, when the Australian Shepherd Club of America was formed and the registry was started.