The Standard Schnauzer is the prototype from which the other two were bred. From the middle ages on they guarded the livestock and family members. They are descended from European herding and guard dogs. As a distinctive breed, they appear in pictures of the 14th and 15th centuries. As far as can be determined they were bred from the Gray Wolf Spitz, the German poodle (pudel) and the Wirehaired Pinscher. About the middle of the 19th century German dog enthusiasts took an interest in the Schnauzer. Dog breeders experimented by crossing them with other breeds. First the Miniature Schnauzer was developed, then the Giant Schnauzer.