The origins of the British Shorthair most likely date back to the first century AD, making it one of the most ancient identifiable cat breeds in the world. It is thought that the invading Romans initially brought Egyptian domestic cats to Great Britain; these cats then interbred with the local European wildcat population. Over the centuries, their naturally isolated descendants developed into distinctively large, robust cats with a short but very thick coat, the better to withstand conditions on their native islands. Based on artists' representations, the modern British Shorthair is basically unchanged from this initial type.
Selective breeding of the best examples of the type began in the nineteenth century, with emphasis on developing the unusual blue-grey variant called the "British Blue" or "English type" (to distinguish it from the more fine-boned "Russian type") in particular. Some sources directly credit UK artist and pioneering cat fancier Harrison Weir with the initial concept of standardizing the breed; others suggest a group of breeders may have been involved. The new British Shorthair was featured at the first-ever cat show, organised by Weir and held at the Crystal Palace in London in 1871, and enjoyed great initial popularity.
By the 1890s, however, with the advent of the newly imported Persian and other long-haired breeds, the British Shorthair had fallen out of favour, and breeding stock had become critically rare by World War I. At least partially to alleviate this, British Shorthair breeders mixed Persians into their bloodlines. The genes thus introduced would eventually become the basis for the British Longhair; at the time, however, any long-haired cats produced were placed into the Persian breeding program. As all cats with the "blue" colouration were then judged together as variants on a de facto single breed, the Blue Shorthair, outcrossings of the British with the Russian Blue were also common.
After the war, in an attempt to maintain the breed standard, the GCCF decided to accept only third-generation Persian/British Shorthair crosses. This contributed to another shortage of pure breeding stock by WWII, at which point the Persian and Russian Blue were reintroduced into the mix. British Shorthair breeders also worked with the French Chartreux, another ancient breed, which although genetically unrelated to the British Blue is a very similar cat in appearance. After the war, breeders worked to re-establish the true British type, and by the late 1970s the distinctive British Shorthair had achieved formal recognition from both the American Cat Fanciers' Association (CFA) and The International Cat Association (TICA). According to the GCCF's 2013 registry data, it is once again the most popular pedigreed breed in its native country
The British Shorthair is a powerful but compact cat that should give an overall impression of neatly balanced sturdiness, having a broad chest, strong thick-set legs with rounded paws and a medium-length, blunt-tipped tail. The head is likewise massive and distinctively rounded, with a short muzzle, broad cheeks (most noticeable in mature males, who tend to develop prominent jowls) and large round eyes that are deep coppery orange in the British Blue and otherwise vary in colour depending on the coat. Their medium-sized ears are broad at the base and should be set widely, not disturbing the overall rounded contours of the head.
They are slow to mature in comparison with most cat breeds, reaching full physical development at approximately three years of age. Unusually among domestic cats they are a noticeably sexually dimorphic breed, with males averaging 9–17 lb (4.1–7.7 kg) and females 7–12 lb (3.2–5.4 kg)
Coat and colour
The British Shorthair's coat is one of the breed's defining features. It is very dense but does not have an undercoat, thus the texture should be plush rather than woolly or fluffy, with a definitely firm, "crisp" pile that breaks noticeably over the cat's body as it moves.
Although the British Blue remains the most familiar variant, British Shorthairs have been developed in many other colours and patterns. Black, blue, white, red, cream, silver, golden and—most recently—cinnamon and fawn are accepted by all official standards, either solid or in colourpoint, tabby, shaded and bicolour patterns; the GCCF and TICA also accept chocolate and its dilute lilac, disallowed in the CFA standard. All colours and patterns also have tortoiseshell variants
They are an easygoing but noticeably dignified breed, not as active and playful as many but sweet-natured and devoted to their owners, making them a favourite of animal trainers. They tend to be safe around other pets and children since they will tolerate a fair amount of physical interaction, but as a rule do not like to be picked up or carried. They require only minimal grooming and take well to being kept as indoor-only cats; however they can be prone to obesity unless care is taken with their diet
The UK breed committee considers the British Shorthair a long-lived cat, with a life expectancy of 14-20 years. Vet clinic data from England shows a median lifespan of 11.8 years. Swedish insurance data puts the median lifespan of the breed at >12.5 years. 82% of British Shorthairs lived to 10 years or more and 54% lived to 12.5 years or more.
Hypertrophic cardiomyopathy (HCM) can be a problem in the breed. A Danish prevalence study with more than 329 cats showed that 20.4% of males and 2.1% of the females had HCM. On top of this 6.4% of males and 3.5% of females were judged to be equivocal. HCM testing of males used for breeding is now mandatory for breeders organized under the Danish Fife member, Felis Danica.
The breed is thought to be at high risk of polycystic kidney disease (PKD). A DNA test lab has noted a significant decrease of the PKD mutations in tested populations. Carrier frequency is now at 1%