The English word squire comes from the Old French escuier (modern French écuyer), itself derived from the Late Latin scutarius ("shield bearer"), in medieval or Old English a 'scutifer].. The Classical Latin equivalent was armiger, "arms bearer". One became a squire at the age of 13 or 14.
A squire was originally a young man who aspired to the rank of knighthood and who, as part of his development to that end, served an existing knight as his attendant or shield carrier. If he proved his loyalty in battle, he would have a dubbing, an official ceremony to become a knight. However, during the Middle Ages the rank of the squire came to be recognized in its own right and, once knighthood ceased to be conferred by any but the monarch, it was no longer to be assumed that a squire would in due course progress to be a knight. The connection between a squire and any particular knight also ceased to exist, as did any shield carrying duties.
In the post-mediaeval world, the title of esquire came to belong to all men of the higher gentry; an esquire ranked socially above a gentleman but below a knight. In the modern world, where all men are assumed to be gentlemen, the term has correspondingly often been extended (albeit only in very formal writing) to all men without any higher title. It is used post-nominally, usually in abbreviated form: "Thomas Smith, Esq.", for example.
Squires were gentlemen with a coat of arms and were often related to peers. Many could claim descent from knights and had been settled in their inherited estates for hundreds of years. The squire usually lived at the village manor house and owned an estate comprising the village with the villagers being his tenants. If the squire "owned the living" (i.e. -- "was patron") of the parish church—and he often did—he would choose the rector, a role often filled by a younger son of the squire. Some squires also became the local rector themselves and were known as squarsons—a combination of the words squire and parson. The squire would also have performed a number of important local duties, in particular that of justice of the peace or Member of Parliament. Such was the power of the squires at this time that modern historians have created the term squirearchy. Politically, during the 19th century squires tended to be Tories whereas the greatest landlords tended to be Whigs.
The position of squire was traditionally associated with occupation of the manor house, which would often itself confer the dignity of squire. It is unclear how widely the village squire may still be said to survive today; but where it does, the role is likely more dependent upon a recognition of good manners, lineage and long family association rather than land, which, while relevant, is nowadays likely to be considerably smaller than in former years due to high post-war death duties and the prohibitive costs associated with maintaining large country houses.
In Scotland, whilst Esquire and Gentleman are technically correctly used at the Court of the Lord Lyon, the title Laird, in place of squire, is more common. Moreover, in Scotland Lairds append their territorial designation to their names as was traditionally done on the continent of Europe (e.g., Donald Cameron of Lochiel). The territorial designation fell into disuse in England early on, save for peers of the realm.
The linguistic and social development of squire is paralleled by that of the German junker, which originally meant "young lord" and denoted the poorer and unimportant part of the aristocracy, but "went up in the world" in much the same time as squire did in England.
The term 'squire' is sometimes used, particularly in cockney slang, by men when addressing another man. In this context it is interchangeable with other slang terms such as 'mate', 'pal' or 'chum', but possibly less familiar (i.e. used when the person addressed isn't known to the speaker) and/or when there is an implied subordinate relationship to the person being addressed. This usage crops up frequently in comedy sketches by Monty Python, et. al. Example: "Yes squire, what can I do for you?".
In earlier years in the U.S. the title squire was given to a Justice of the Peace, for example Squire Jones. It was also used to mean Justice of the Peace as in the expample "He was taken before the squire."
In English literature, people usually remember Squire Trelawney, one of the many literary creations of Robert Louis Stevenson, a Cornish squire who protects young Jim Hawkins from the murderous pirates who are seeking his treasure map, and helps him engage a crew to sail to Treasure Island.
William Makepeace Thackeray's depiction of a squire in Vanity Fair showed the class to be lecherous, ill-educated, badly mannered relics of an earlier age. However, he clearly shows their control of the life of the parish.
There are numerous other squires in English literature. King Arthur in The Sword in the Stone was Sir Kai's squire as a boy. Others include Squire Hamley in Elizabeth Gaskell's Wives and Daughters; the squire in The Canterbury Tales; and Squire Allworthy (based on Ralph Allen) in the novel Tom Jones by Henry Fielding, who was himself a squire and magistrate.
In the collection of short novels SMM7: Adventures of a Quantity Surveyor, Sir Hector and his gathering of associates, Rab Van Der Crab, Robberto, MCAP, Hamido Amigo, Large Ally, Obi Wan Shinobi and Verererek are known as the Squires. They often embark on fantastic adventures to far off lands, across the border and over treacherous waters. A trip to a mysterious island in Croatia is surely a possibility .