Dog fighting is a physical fight between canines, sometimes involving the pitting of two dogs against each other for the entertainment of spectators, and for the purpose of gambling. It is considered by some to be a sport, as the dogs are judged on their wrestling, bite and gameness while onlookers root and place bets. Dog fighting is accepted in some countries but is illegal within the United States and other countries.
As with all domestic dogs, the ancestors of all breeds were wolves. The foundation breed of the fighting dog was, in its outward appearance, a large, low, heavy breed with a powerful build and strongly developed head.
Dog breeding in its earliest stages was carried out systematically, with the desire for specialization. It is believed that the development of individual breeds took place in narrow geographic areas, corresponding to the performance required in these regions. Selection for performance, complemented by the breeding for suitable body forms, leads to the formation of breeds. The task of the fighting dog demanded specific basic anatomical traits and temperamental features. The anatomy of the fighting dog requires an imposing outward form to instill fear, with the foundation breed naturally large, low-slung, heavy, powerfully built, with a strongly developed head, powerful biting apparatus and a threatening voice. The goal is to breed a dog that will attack animals but is docile and affectionate toward humans. All breeds with a character suitable for protecting humans and fighting wild animals may be considered for dogfighting.
Many breeds that were once associated with dog fighting have been developed into excellent family and show dogs. Pure breeds such as the English Bull Terrier and the Staffordshire Bull Terrier were popular as fighting dogs, but were originally developed as bait dogs. Other pure breeds including the Irish Terrier, the bulldog, the Kerry Blue Terrier and the Parson Russell Terrier were used for fighting along side their original use in vermin control and other farm work.
Dog fighting has been documented in the recorded history of many different cultures, and is presumed to have existed since the initial domestication of the species. Many breeds have been bred specifically for the strength, attitude, and physical features that would make them better fighting dogs.
Scholars speculate that large-scale human migration, the development of trade, and gifts between royal courts of valuable fighting dogs facilitated the spread of fighting dog breeds. There are many accounts of military campaigns which utilized fighting dogs, as well as royal gifts in the form of large dogs.
Blood sports involving the baiting of animals has occurred since antiquity, most famously at the Colosseum in Rome during the reign of the Roman Empire. However, in contemporary times, it is most associated with the English, who pursued it with utmost earnestness, which was barely known elsewhere in the world. For over six hundred years the pastime flourished, reaching the peak of its popularity during the sixteenth century. The various animal types involved in the bait allowed for the breed specialization and basic anatomical forms of fighting dogs, which we see today.
Dog fighting has been popular in many countries throughout history and continues to be practiced both legally and illegally around the world.
Dog fighting began in Japan before the end of the Kamakura period. According to historical documents, Hōjō Takatoki, the 14th shikken (shogun's regent) of the Kamakura shogunate was known to be obsessed with dog fighting, to the point where he allowed his samurai to pay taxes with dogs. At this time, dog fighting was called inuawase.
Dog fighting was considered a way for the Samurai to retain their aggressive edge during peaceful times. Several daimyo, such as Chosokabe Motochika and Yamauchi Yodo, both from Tosa Province (present-day Kochi Prefecture), were known to encourage dog fighting. Dog fighting was also popular in Akita Prefecture, which is the origin of the Akita breed.
Dog fighting evolved in Kochi to a form that is called Tōken (闘犬). Under modern rules, dogs fight in a fenced ring until one of the dogs barks, yelps, or loses the will to fight. Owners are allowed to throw in the towel, and matches are stopped if a doctor judges it is too dangerous. Draws usually occur when both dogs won't fight or both dogs fight until the time limit. There are various other rules, including one that specifies that a dog will lose if it attempts to copulate. Champion dogs are called yokozuna, as in sumo. With generic animal protection laws in place, dog fighting is not specifically banned in Japan, except in Tokyo, and can be seen in Kochi. Currently, most fighting dogs in Japan are Tosa, which is a breed that was developed in Kochi. Dog fighting does not have strong links to gambling in Japan.
Dog fighting is widely practiced in much of Latin America, especially in Argentina, Colombia and many parts of Brazil. The Dogo Argentino is by far the most common breed involved in the bloodsport. The Fila Brasileiro is also used, but rarely. The American Pit Bull Terrier is another breed that is commonly involved in dog fighting circuits. The Dogo Cubano and dogo cordoba were used for fighting a century ago, but have become extinct.
Main article: Dog fighting in the United States
Dog fighting is illegal in all North American countries.
According to a study by the College of Law of the Michigan State University published in 2005, in the United States, dog fighting was once completely legal and was sanctioned and promoted during the colonial period (1600s through 1776) and continuing through the Victorian era in the late 19th century. However, by the early twentieth century, the brutality inherent in dog fighting was no longer tolerated by American society. It has become increasingly outlawed, a trend which has continued into the 21st century.
As of 2007, dog fighting is a felony in 48 states and a misdemeanor in Idaho and Wyoming. In most states, it is against the law (and often a felony) to even attend a dog fighting event, regardless of direct participation. According to authorities, dog fighting is increasingly practiced by gangs, and is linked to other unlawful activities, such as gambling.
Despite legality issues, dogs are still commonly used for fighting purposes all across the continent. The American Pit Bull Terrier is the most popular breed used for fighting, but foreign breeds, such as the Dogo Argentino (used widely in South America) and Presa Canario (used in Spain) are also gaining popularity.
Dog fighting is widely practiced throughout rural India. Indian feudal lords take pride in pitting their dogs against a rival's, or they make the dogs fight with bears. However, dog fighting is illegal as defined by Indian law. In addition, it is illegal to possess dogfighting materials such as videos, or to attend an event that subjects an animal to cruel treatment. But since bribery is a common practice, many indian officials prefer to take money instead of prosecuting animal cruelty.
Although animal cruelty laws exist in Russia, dog fighting is widely practiced. Laws prohibiting dogfights have been passed in certain places, and in others dogfights are legally held under the supervision of the All-Russian Association of Russian Volkodavs. Temperament tests, which are a common and relatively mild form of dog fighting used for breeding purposes, are fairly commonplace. 
During the time of Roman Britain, there were Pugnaces Britanniae or war dogs, mostly used in battle but later used for dog fighting contests in the amphitheatre. As early as 1154, in the reign of Henry II, bull-baiting and bear-baiting with dogs was a popular amusement.
Breeding allowed for a specialized breed in the form of the now extinct original Old English Bulldog. The contemporary recreation of the breed is called the Olde English Bulldogge.
The Cruelty to Animals Act 1835 in the United Kingdom was the first legislation in the world that made dogfighting illegal; however, it continued in London long after and continues to occur in rural areas of the United Kingdom. Dog fighting is now illegal in all first world countries and many third world countries. However, dog fighting still occurs across the globe. To combat dog fighting the designation of so-called dangerous dog breeds, Breed Specific Legislation (BSL
) has been passed. For those interested in fighting dogs, outlawing their specific breeds encourages them to find substitute breeds suitable for fighting forces them to take their breeds out of the public eye.
Despite periodic dog-fight prosecutions, the illegal canine pit battles continued. Sporting journals of the 18th and 19th centuries depict the Black Country and London as the primary English dog fight centres of the period. Dog fighting was also practiced in many areas of Ireland.
Dog fighting is still popular in certain areas of England, with a large underground following. Largely as the result of attacks on children, police have increased enforcement activities.