(Fr. escu, a shield, from the Lat. scutum, from the Gk. σκῦρος, a hide, with which shields were anciently covered) originally denoted the attendant or shield-bearer of a knight, and hence he was called escuier in French, and scutifer or armiger in Latin. In the days of chivalry the esquire was second in rank to the knight. Aspirants to knighthood passed through several gradations of service or apprenticeship to arms as page, and esquire or bachelor, previous to being admitted to that honour. The esquire had several privileges, such as the right of wearing a sword and defensive armour, which last, however, differed from the full panoply of a knight; and he likewise might use heraldic bearings on his escutcheon or shield. There was also another class of esquires, consisting of those tenants by knight's service who had a right to claim knighthood, and who possessed many of its privileges. Such was the German Ritter, as distinguished from the Ritter geschlagen or dubbed knight.

Respecting the title of esquire in modern times, it is somewhat unsettled, says Blackstone (book i. chap. 12), what now constitutes a right to this distinction, or who is a real esquire; for it is not an estate, however large, that confers this rank upon its owner. In some old writers mention is made of esquires by creation, by investiture with a silver collar of SS., to which ceremony was added the putting on of a pair of silver spurs. It appears that in England this title appertains by right of birth to the following persons: the sons of younger sons of dukes and marquises; the younger sons of earls, viscounts, and barons, and their eldest sons; the eldest sons of baronets and of knights. The following also are reputed esquires: officers of the queen's court and household; officers of the navy and army, down to the captain inclusive; doctors of law; sergeants and counsellors at law; physicians; justices of the peace while in commission; and the sheriffs of counties for life. The heads of many ancient families likewise are deemed esquires by prescription. The title, however, is now usually given to all professional and literary men, and is very generally affixed, as in the superscription of letters, to the names of persons who live in the rank of gentlemen. Hence the distinction it formerly conferred is virtually destroyed.