Lapdogs historically were kept in many societies around the world by individuals with leisure time, as docile companion animals with no working function. Today, most lapdog breeds fall into the Toy breed group.
Some lapdogs have been bred for extremes of small size, such as the Russian and Mexican varieties shown below. Anatomically, lapdogs show distinct differences from their full-sized counterparts. The skull of the immature Russian lapdog (Bolonka) specimen is approximately the size of a table-tennis ball and shows the relatively short muzzle and high forehead. Many lapdogs are bred to retain puppy-like traits (neoteny) such as folded ears. Body proportions may also have changed, resulting in relatively short legs and large heads. They may also have traits that resemble human babies: size and weight, high forehead, short muzzle and relatively large eyes. Although selective breeding for such traits can have detrimental effects on tear ducts, dentition, and breathing, such traits also serve to cause pet owners to derive more satisfaction from their pet relationship, as the pet owners may view dogs with this appearance as surrogate babies.
Lapdogs have been used for pets, fashion accessories, status symbols, and to provide warmth for the wealthy and fashionable. Lapdogs were also used in earlier times to attract fleas away from their owners. Some lapdogs were developed as pets while others, among the terrier group, for example, were first bred for active work. Most kennel clubs list lapdog terriers in the Toy Group.
Recent genetic study confirms that the Pekingese lapdog, bred in ancient China to fit inside the sleeves of a man's robe, is one of the oldest breeds of dog. For centuries, they could be owned only by members of the Chinese Imperial Palace.
According to the 1948 publication Dogs In Britain, A Description of All Native Breeds and Most Foreign Breeds in Britain by Clifford LB Hubbard, the Sleeve Pekingese was (in Hubbard's time) a true miniature of the standard-sized Pekingeses and was also known as the Miniature Pekingese. The name Sleeve Pekingese came from the custom of carrying these small dogs in the capacious sleeves of the robes worn by members of the Chinese Imperial Household. Hubbard indicated that this tradition appeared to be early Italian rather than Chinese, but its adoption by the Chinese Imperial Household led to dogs being bred as small as possible and to practices aimed at stunting their growth: giving puppies rice wine, holding new-borns tightly for hours at a time or putting the puppies into tight-fitting wire mesh waistcoats. These practices were apparently forbidden by the late Dowager Empress Tzu Hsi.
In Hubbard's time, the term Sleeve was applied in Britain to a miniature Pekingese no more than 6-7 pounds in weight, often appearing to be only about 3-4 pounds. Mrs Flander’s Mai Mai weighed only a little over 4 pounds and many other breeders had bred true miniatures of of a similar size. Hubbard noted that miniatures sometimes appeared in litters bred from full-sized Pekingese and were exhibited in classes for dogs less than 7 pounds at the major dog shows in Britain. At that time, the Sleeve Pekingese had a strong following with the most popular colours being cream and white.
In the book De Canibus Britannicus published in English in 1576, the author describes lapdogs as a type of dog, "Spaniel Gentle or Comforter". Ancestors of the Cavalier King Charles Spaniel were a type of "Spaniel Gentle" kept by English nobility in the 1600s.
The Russian Lapdog and the Mexican Lapdog' were not breeds in the modern sense, but were types of small dogs from Russia and Mexico respectively. The individuals shown here are juveniles and are shown with a Griffon Bruxellois to indicate scale. The immature Mexican Lapdog specimen is approximately the size of a golden hamster. Adult specimens are not on display. During the 19th Century it was fashionable to mount immature specimens to look like adults, giving a false impression of adult size.
From: The Illustrated Natural History (Mammalia) by the Rev John George Wood, 1853
The term lapdog is also used to describe a submissive person, such as a "yes" man, or an institution that very easily controlled (as in the lapdog press in contrast to the tougher, more confronting watchdog press).