It is not known what exactly the Chihuahua was bred for. Most theories show that the breed originated somewhere in Mexico.
Most people believe that the Chihuahua was first bred in Chihuahua, Mexico. Hence the name it was given. The breed might have been bred by the Mayans or Toltecs between 1800 B.C. and 900 A.D. The Techichi seems to be the breed that came first. It was then bred down in size. Other theorists believe that these two breeds are the same. The Chihuahua is one of the longest registered breeds in the American Kennel Club. It was first recognized as an AKC breed in 1904.