Description of a Tibetan Mastiff.

This is an ancient breed, descended from very early large Tibetan dogs from which most, if not all, of today's Mastiff-type and Molossuses are descended. Some of the modern breeds thought to have Tibetan Mastiff ancestry include the St. Bernard,Leonberger, the Newfoundland, the Kuvasz, and even the toy dog breed, the Pug, which itself was a well-established breed before the 1500s [citation needed]. Marco Polo encountered the large Tibetan dogs in his travels and described them as "tall as a donkey with a voice as powerful as that of a lion." They were used as guard dogs outside the sacred city of Lhasa.

The breed originated in Tibet as a flock dog and guard dog and it makes an excellent family protector. In the early 19th century, King George IV owned a pair, and there were enough of the breed in England in 1906 to be shown at the 1906 Crystal Palace show. However, during the war years, the breed lost favor and focus and nearly died out in England. Then, with the 1959 occupation of Tibet, the breed became nearly extinct, with a chosen few exported in the 1960s and 1970's to found the American and European based bloodlines that thrive today.

Gaining in popularity worldwide, there are more and more active breeders, although the breed is still considered somewhat uncommon. Initially the breed suffered because of the limited genepool from the original stock, but today's reputable breeders work hard at reducing the genetic problems through selective breeding and the international exchange of new bloodlines.