Chihuahua

History: The Chihuahua, the smallest breed of dog has a controversial history of origin. On eschool of thought has it that the dog originated from China and was introduced to the New world by the Spanish armies of Hernando Cortes in 1519; the other school of thought postulates that the Chihuahua is a descendant of the Techichi, a dog bred by the ancient Toltec civilization of Mexico for sacrifice. Whatever the case, the truth probably lies somewhere in between. The native sacrificial dog, the Techichi likely cross-bred with the small hairless Chinese dogs that were introduced by Spanish.

What is well documented though is that in 1850 three very small dogs were "discovered" in Chihuahua, Mexico (hence the name) and were introduced to the United States. The Chihuahua breed never caught on in the US until it was popularized by Xavier Cugat (aka the rhumba king) who appeared very often in public with one as his companion!