The use of dogs as guardians is well known since ancient times. The Romans used to put mosaics (Cave canem mosaics) at the entrance of the houses to warn visitors and intruders of the presence of dangerous dogs at the property.
One of the first dog types used as guardians were the ancestral Mastiff-type landraces of the group known as Livestock guardian dogs which protected livestock against large predators such as wolves, bears and leopards. Orthros is a famous example of a livestock guardian dog from the Greek mythology known for guarding Geryon’s red cattle.
Some ancient guard dogs in more urban areas, such as the extinct bandages, were chained during the day and released at night to protect properties, camps and villages.