The head must be round (also when viewed in profile), the skull is broad with a well rounded forehead and dome.
The ears are small and placed rather deep .
The nose is very short in the Persian of today and must be broad, it has a stop - in some associations it must be a break - between the eyes, in the so called Peke-Face Persians the nose has a deep break between the eyes.

The eyes are large and round and set wide apart (to give that certain baby look). The eye colour is different in different coat colours: Orange eyes are found in solid colours, tabbies, white, smoke, bi-colour. Blue eyes are found in white, bi-colour and Colourpoints (Note: The blue eye colour of a Colourpoint is genetically different from the blue eye colour in a white cat!). Green eyes are found in black/blue silver shaded and silver tabbies.
The jaws are broad, the bite must be level.

The coat is soft and very long, with a dense undercoat. The coat is long all over the body, also including the shoulders. Around the neck there is an immense ruff with a long frill in winter covering almost the entire length of the front legs.

The tail is short and bushy, the tail tip is rounded and the hairs form a round brush.

History

Angora cats and Persian seem to have the same origin, because there was not made a clear difference between Angora cats and Persian cats.
The first Angora cats were brought to Italy from Asia Minor in 1620, imported by Pietro Della Valle, at the same time they arrived also in France, imported by Nicolas-Claude Fabri de Peiresc.
Read more about at:
Pre-history of Angora cats
History of the Angora cat
L'Histoire Naturelle, Comte de Buffon, Band VI

Thus the Persian or the Angora (mostly the white cats) were also called French cats in England.

Harrison Weir makes a clear difference between the Angora cat and the Persian cat in his book Our cats and all about them, 1889.
Page 16: LONG-HAIRED CATS
"There are several varieties the Russian, the Angora, the Persian, and Indian."

Page 24: Description of the Persian cat
"THIS differs somewhat from the Angora, the tail being generally longer, more like a table brush in point of form, and is generally slightly turned upwards, the hair being more full and coarser at the end, while at the base it is somewhat longer. The head is rather larger, with less pointed ears, although these should not be devoid of the tuft at the apex, and also well furnished with long hair within, and of moderate size. The eyes should be large, full, and round, with a soft expression ; the hair on the forehead is generally rather short in comparison to the other parts of the body, which ought to be clothed with long silky hair, very long about the neck, giving the appearance of the mane of the lion. The legs, feet, and toes should be well clothed with long hair and have well-developed fringes on the toes, assuming the character of tufts between them. It is larger in body, and generally broader in the loins, and apparently stronger made, than the foregoing variety, ..."

Page 140 and following: LONG-HAIRED CATS POINTS OF EXCELLENCE
On the following pages the standard of the different colors is described, this standard describes the Angora, Persian and Russian Longhair:
white, black, blue, grey (which color it is, is unclear), red and all other solid colors
brown, blue, silver, light grey and white tabby, chocolate, mahagony and red or yellow tabby (described is the mackerel pattern), whatever is meant by light grey and white tabby,
there existed also the spotted pattern for these colors.

Persian cat Tim of Mr. A. A. Clarke

Gradually the body became more cobby, the ears smaller and the head larger and broader giving more pre-eminence to the body type of the French cats.
By the turn of the century to 1900 the breed was exported to North America and was recognized by all registries.
Read about it in Frances Simpson The Book Of The Cat, 1903, who describes the various clubs in North America quite in detail.

The Blue is one of the oldest colors, and was already presented in the show in Crystal Palace in London in 1871, it became soon very popular as Queen Victoria is said to have owned two blue Persian cats.
Thus in 1901 the Blue Persian Cat Society was founded.

Frances Simpson: Blue Persian, presented to Queen Victoria

By 1901 the colors recognized in Britain were black, blue, white, orange (today's red self and red tabby), cream, sable (this colour cannot be clearly identified, but its description sounds like the ancestors of today's Goldens), smoke, tabby, spotted, chinchilla, tortieshell, bi-colour and tri-colour (today's tortie with white respective Calicos as they are called in North America).
Read about it at 'Frances Simpson, page 60.

The first smoke Persians were registered as a separate breed class in Britain in 1893.
One of the most famous Chinchillas was Silver Lambkin. Today silver Chinchillas and Silver Shaded are recognized in black/blue tipped, chocolate/lilac tipped, red/cream tipped and tortie tipped, the color variants with red are often referred as cameos.
The Silver and Smoke Persian Cat Society was founded in 1900.

Silver Lambkin, description see at Frances Simpson, page 148

Originally known as magpie cats, popular in shorthair first,  the Bi-colours and Calicos were recognized in Britain in 1966 and soon afterwards in North America.

Peke-face Persians were recognized as separate variety (colour class) in the USA and Canada, they are only bred in red and red tabby.

The Colourpoint, often referred as Himalayan, in former times up to 1950 called Khmer, is a man-made breed, resulting from cross breeding between Siamese and long-haired white cats done by the Swedish geneticist T Tjebbes in 1924. This breeding program was continued in North America in 1931 by Virginia Cobb (Newton cattery) and Dr. Clyde Kyler (Harvard Medical School), breeding black Persians to Siamese, where they got black shorthaired kittens, which were breed together, thus resulting in the first longhair pointed cat born in 1936, named Newton's Debutante.
Siamese-Persian Cats, Clyde E. Kyler, Virginia Cobb, Journal of Heredity, v. 27, No. 9, Sept. 1936
Crosses with Siamese Cats, K. Tjebbes, Journal of Genetics, V. 14, p. 335, 1924

In 1955 the breed was recognized by GCCF as Colourpoint.
Mr. Brian Stirling-Webb (Briarry cattery) and Mrs. SM Harding (Mingchiu cattery) have to be mentioned, who put a lot of effort into the recognition of this variety.

Briarry Gohar bred by Brian Stirling-Webb

Breeding Siamese to Persians brought up also the chocolate Longhair in 1957 (Briarry Bruno, parents: Gadeford Bagheera, chocolater shorthair, and Briarry Frolic, blue-cream shorthair), and the lilac Longhair (Mingchiu Lilac, father Briarry Bruno).

Breeding of pedigreed Himalayans in the United States started in 1950.
There must be mentioned:
Ben and Ann Borrett, Chestermere cattery (called after their cattle farm in West-Canada), who purchased several cats from Stirling-Webb. In 1957 they exhibited two imported cats in Calgary, Alberta, Canada at an ACFA show. They are also responsible for the standard of the Himalayan.
Marguerita Goforth, an artist from California, USA, Goforth cattery, bred with Princess Himalayan Hope, a sealpoint longhaired female of her friend, which came from the shelter San Diego Humane Society. Mrs. Goforth used the standard of the Borretts.
The Himalayans were recognized by all major associations in North America in 1961.
In 1964 the redpoint and tortie point Himalayan was recognized in the US. In 1984 the Himalayan was re-distributed by CFA to the Persian as a color group (division).

Temperament

The Persian has a quiet, very gentle and sweet personality. The cat is affectionate to people and rather little talkative. Everything is done cautiously, but yet they are very alert, they are not seriously in a hurry. The Persian is to be considered by many as the aristocrat in the cat fancy.

Grooming

Persians have a very thick woolly undercoat, but this goes hand in hand with matting. They have to be combed and brushed constantly to keep their coat free from knots and mats. They require daily care. Do not plan to have a Persian unless you have enough time for grooming. You have to give them a bath on a regular basis to keep their impressing and wonderful coat shiny and silky.