Gin is a spirit which derives its predominant flavour from juniper berries (Juniperus communis). From its earliest origins in the Middle Ages, gin has evolved from use in herbal medicine to an object of commerce in the spirits industry. Gin was developed on the basis of the older jenever, and became popular in Great Britain (particularly in London) when William of Orange, leader of the Dutch Republic, occupied the English, Scottish, and Irish thrones with his wife Mary. Gin is one of the broadest categories of spirits, represented by products of various origins, styles, and flavour profiles that all revolve around juniper as a common ingredient.

The name gin is a shortened form of the older English word genever, related to the French word genièvre and the Dutch word jenever. All ultimately derive from juniperus, the Latin for juniper.

The Dutch physician Franciscus Sylvius is often falsely credited with the invention of gin in the mid 17th century, although the existence of genever is confirmed in Philip Massinger’s play The Duke of Milan (1623), when Sylvius would have been about nine years old. It is further claimed that English soldiers who provided support in Antwerp against the Spanish in 1585, during the Eighty Years’ War, were already drinking genever for its calming effects before battle, from which the term Dutch Courage is believed to have originated.

The earliest known written reference to genever appears in the 13th century encyclopaedic work Der Naturen Bloeme (Bruges), with the earliest printed recipe for genever dating from 16th century work Een Constelijck Distileerboec (Antwerp).

By the mid 17th century, numerous small Dutch and Flemish distillers (some 400 in Amsterdam alone by 1663) had popularized the re-distillation of malt spirit or malt wine with juniper, anise, caraway, coriander, etc., which were sold in pharmacies and used to treat such medical problems as kidney ailments, lumbago, stomach ailments, gallstones, and gout. Gin emerged in England in varying forms as of the early 17th century, and at the time of the Restoration, enjoyed a brief resurgence. When William of Orange, ruler of the Dutch Republic, occupied the British throne with his wife Mary in what has become known as the Glorious Revolution, gin became vastly more popular, particularly in crude, inferior forms, where it was more likely to be flavoured with turpentine as an alternative to juniper.

Gin drinking in England rose significantly after the government allowed unlicensed gin production, and at the same time imposed a heavy duty on all imported spirits such as French brandy. This created a larger market for poor-quality barley that was unfit for brewing beer, and in 1695-1735 thousands of gin-shops sprang up throughout England, a period known as the Gin Craze. Because of the low price of gin, when compared with other drinks available at the same time, and in the same geographic location, gin began to be consumed regularly by the poor. Of the 15,000 drinking establishments in London, not including coffee shops and drinking chocolate shops, over half were gin shops. Beer maintained a healthy reputation as it was often safer to drink the brewed ale than unclean plain water. Gin, though, was blamed for various social problems, and it may have been a factor in the higher death rates which stabilized London’s previously growing population. The reputation of the two drinks was illustrated by William Hogarth in his engravings Beer Street and Gin Lane (1751), described by the BBC as “arguably the most potent anti-drug poster ever conceived.” The negative reputation of gin survives today in the English language, in terms like “gin mills” or the American phrase “gin joints” to describe disreputable bars, or “gin-soaked” to refer to drunks. The epithet “mother’s ruin” is a common British name for gin, the origin of which is the subject of ongoing debate.

The Gin Act 1736 imposed high taxes on retailers and led to riots in the streets. The prohibitive duty was gradually reduced and finally abolished in 1742. The Gin Act 1751 was more successful, however; it forced distillers to sell only to licensed retailers and brought gin shops under the jurisdiction of local magistrates. Gin in the 18th century was produced in pot stills, and was somewhat sweeter than the London gin known today.

In London in the early 18th century, much gin was distilled legally in residential houses (there were estimated to be 1,500 residential stills in 1726) and was often flavoured with turpentine to generate resinous woody notes in addition to the juniper. As late as 1913, Webster’s Dictionary states without further comment, ” ‘common gin’ is usually flavoured with turpentine”.

Another common variation was to distill in the presence of sulphuric acid. Although the acid itself does not distil, it imparts the additional aroma of diethyl ether to the resulting gin. Sulphuric acid subtracts one water molecule from two ethanol molecules to create diethyl ether, which also forms an azeotrope with ethanol, and therefore distils with it. The result is a sweeter spirit, and one that may have possessed additional analgesic or even intoxicating effects — see Paracelsus.

Dutch or Belgian gin, also known as jenever or genever, evolved from malt wine spirits, and is a distinctly different drink from later styles of gin. Schiedam, a city in the province of South Holland, is famous for its jenever-producing history. The oude (old) style of jenever remained very popular throughout the 19th century, where it was referred to as “Holland” or “Geneva” gin in popular, American, pre-Prohibition bartender guides.

The 19th century gave rise to a style of gin referred to as Old Tom Gin, which is a softer, sweeter style of gin, often containing sugar. Old Tom gin faded in popularity by the early 20th century.

The invention and development of the column still (1826—31) made the distillation of neutral spirits practical, thus enabling the creation of the “London dry” style that evolved later in the 19th century.

In tropical British colonies gin was used to mask the bitter flavour of quinine, which was the only effective anti-malarial compound. Quinine was dissolved in carbonated water to form tonic water; the resulting cocktail is gin and tonic, although modern tonic water contains only a trace of quinine as a flavouring. Gin is a common base spirit for many mixed drinks, including the martini. Secretly produced “bathtub gin” was available in the speakeasies and “blind pigs” of Prohibition-era America as a result of the relative simple production.

Sloe gin is traditionally described as a liqueur made by infusing sloes (the fruit of the blackthorn) in gin, although modern versions are almost always compounded from neutral spirits and flavourings. Similar infusions are possible with other fruits, such as damsons or beach plums.

Since 2009 the second Saturday in June has been designated as World Gin Day.

Although several different styles of gin have evolved, it is legally differentiated into four categories in the European Union, which are described as follows.

Juniper-flavoured spirit drinks

This includes the earliest class of gin, which is produced by pot distilling a fermented grain mash to moderate strength (e.g. 68% ABV), and then redistilling it with botanicals to extract the aromatic compounds. It must be bottled at a minimum of 30% Alcohol by volume (ABV). Juniper-flavoured spirit drinks may also be sold under the names Wacholder or Genebra.

Gin

This is a juniper-flavoured spirit made not via the redistillation of botanicals, but by simply adding approved natural flavouring substances to a neutral spirit of agricultural origin. The predominant flavour must be juniper.

Distilled gin

Distilled gin is produced exclusively by redistilling ethanol of agricultural origin with an initial strength of 96% ABV (the azeotrope of water and ethanol) in stills traditionally used for gin, in the presence of juniper berries and of other natural botanicals, provided that the juniper taste is predominant. Gin obtained simply by adding essences or flavourings to ethanol of agricultural origin is not distilled gin.

London gin

London gin is obtained exclusively from ethanol of agricultural origin with a maximum methanol content of 5 grams per hectolitre of 100% ABV equivalent, whose flavour is introduced exclusively through the re-distillation in traditional stills of ethanol in the presence of all the natural plant materials used, the resultant distillate of which is at least 70% ABV. London gin may not contain added sweetening exceeding 0.1 grams of sugars per litre of the final product, nor colorants, nor any added ingredients other than water. The term London gin may be supplemented by the term “dry”.

In the EU, the minimum bottled alcoholic strength for gin, distilled gin, and London gin is 37.5% ABV.

In the United States, gin is defined as an alcoholic beverage of no less than 40% ABV (80 proof) that possesses the characteristic flavour of juniper berries. Gin produced only through distillation or redistillation of aromatics with an alcoholic wash can be further distinguished and marketed as “distilled gin”.

The Canadian Food and Drug Regulation recognizes gin with three different definitions (Genever, Gin, London or Dry gin) that loosely approximate the U.S. definitions. Whereas a more detailed regulation is provided for Holland gin or genever, no distinction is made between compounded gin and distilled gin. Either compounded or distilled gin can be labeled as Dry Gin or London Dry Gin if it does not contain any sweetening agents.

Some legal classifications define gin as only originating from specific geographical areas without any further restrictions (e.g. Plymouth gin, Ostfriesischer Korngenever, Slovenská borovička, Kraški Brinjevec, etc.), while other common descriptors refer to classic styles that are culturally recognized, but not legally defined (e.g., sloe gin and Old Tom gin).

Several different techniques for the production of gin have evolved since its early origins, this evolution being reflective of ongoing modernization in distillation and flavouring techniques. As a result of this evolution, gins can be broadly differentiated into three basic styles.

• Pot distilled gin represents the earliest style of gin, and is traditionally produced by pot distilling a fermented grain mash (malt wine) from barley or other grains, then redistilling it with flavouring botanicals to extract the aromatic compounds. The fermentation of grain mash produces a neutral alcohol (similar to vodka) that is predominately tasteless except for the iconic ethyl alcohol taste. A double gin can be produced by redistilling the first gin again with more botanicals. Due to the use of pot stills, the alcohol content of the distillate is relatively low; around 68% ABV for a single distilled gin or 76% ABV for a double gin. This type of gin is often aged in tanks or wooden casks, and retains a heavier, malty flavour that gives it a marked resemblance to whisky. Korenwijn (grain wine) and the oude (old) style of Geneva gin or Holland gin represent the most prominent gins of this class.
• Column distilled gin evolved following the invention of the Coffey still, and is produced by first distilling high proof (e.g. 96% ABV) neutral spirits from a fermented mash or wash using a refluxing still such as a column still. The fermentable base for this spirit may be derived from grain, sugar beets, grapes, potatoes, sugar cane, plain sugar, or any other material of agricultural origin. The highly concentrated spirit is then redistilled with juniper berries and other botanicals in a pot still. Most often, the botanicals are suspended in a “gin basket” positioned within the head of the still, which allows the hot alcoholic vapours to extract flavouring components from the botanical charge. This method yields a gin lighter in flavour than the older pot still method, and results in either a distilled gin or London dry gin, depending largely upon how the spirit is finished.
• Compound gin is made by simply flavouring neutral spirits with essences or other “natural flavourings” without redistillation, and is not as highly regarded as distilled gin.

Popular botanicals or flavouring agents for gin, besides the required juniper, often include citrus elements, such as lemon and bitter orange peel, as well as a combination of other spices, which may include any of anise, angelica root and seed, orris root, licorice root, cinnamon, almond, cubeb, savory, lime peel, grapefruit peel, dragon eye (longan), saffron, baobab, frankincense, coriander, grains of paradise, nutmeg, cassia bark or others. The different combinations and concentrations of these botanicals in the distillation process cause the variations in taste among gin products.

Chemical research has begun to identify the various chemicals that are extracted in the distillation process and contribute to gin’s flavoring. For example, juniper monoterpenes come from juniper berries. Citric flavors come from chemicals, such as limonene and gamma-terpinene linalool. Spice-like flavors come from chemicals, such as sabinene, delta-3-carene, and para-cymene.

According to the Canadian Food and Drug Regulation, gin is produced through redistillation of alcohol from juniper-berries or a mixture of more than one such redistilled food products.