Coffee: from Ethiopian forests to the world's cafés

Coffea arabica is a natural hybrid of two other coffee species, C. eugenioides and C. canephora (robusta). A genome study published in 2024 dates the hybridisation to between 350,000 and 610,000 years ago, and finds that wild Arabica still grows in the forests of Ethiopia. South-western Ethiopia is the plant's original home. Arabica today supplies about 60 % of the world's coffee.

The best-known story of its discovery is a legend. A goatherd, named Kaldi in the French telling, notices his goats dancing after eating red berries; a monk tries them and finds he can stay awake through night prayers. William Ukers, who collected coffee lore in 1922, already printed it as one legend among several. Modern historians treat it as apocryphal: the museum curator Edward Keall, reviewing the standard history by Ralph Hattox, notes that the goat story has no documentary basis. Keall notes that the plant itself found little favour as a drink in Ethiopia at the time it was taken up in Yemen.

The first reliable evidence of coffee drinking comes from Yemen in the middle of the fifteenth century. Ralph Hattox's history of the coffeehouse, as the museum curator Edward Keall summarises it, shows that groups of mystics there used its stimulating properties in their devotions. The plant had been brought across the Red Sea from Ethiopia, and the 2024 genome study confirms that Arabica cultivation began in Yemen in the fifteenth or sixteenth century, from a narrow pool of plants.

From Yemen the habit moved with merchants to Cairo in the early sixteenth century and to Istanbul by the middle of it. Ukers dates the first two Istanbul coffeehouses to 1554. Coffee was argued over from the start. In Mecca in 1511 the city's superintendent saw men drinking coffee in the precincts of the mosque; after a staged hearing coffee was declared unlawful and burned in the streets. Such rulings did not last. A fatwa was an opinion, not a law. Opposition was often as much about order as religion: city officials worried that coffeehouses, with their crowds and late hours, looked too much like taverns. Hattox also asks whether merchants who lost their spice monopolies after 1492 were looking for a new commodity to sell. Whatever the reasons, the coffeehouse became a fixture of Ottoman city life, a place for conversation, games and news.

Coffee reached Europe as an apothecary's drug and then as a drink. Ukers says a coffee shop opened in Venice in 1683 is certain, while the often-quoted date of 1645 lacks confirmation. In England a coffeehouse opened in Oxford in 1650, and in 1652 Pasqua Rosée, servant of the English merchant Daniel Edwards of Smyrna, opened the first one in London. Paris had to wait for the Café de Procope, which Ukers dates to 1689 (other accounts give 1686).

Europeans wanted their own supply. Around 1600 a few seeds were smuggled out of Yemen to India. The Dutch shipped plants from the Malabar coast to Java in 1696; these were lost to flood and earthquake, and cuttings sent in 1699 took hold. A Java-grown plant reached the Amsterdam botanical garden in 1706, and in 1714 the city gave one to Louis XIV. Its descendants, by Ukers's account, stocked the French colonies. A naval officer, Gabriel de Clieu, carried a plant to Martinique; whether in 1720 or 1723 is disputed. Ukers lists the spread that followed: Saint-Domingue in 1715, Dutch Suriname in 1718, a failed first planting at Pará in Brazil in 1723, Jamaica in 1730 and Rio de Janeiro from 1760. Nearly all Arabica cultivars grown today descend from these few plants: the Dutch line became the Typica group, and a single plant that survived on the French island of Bourbon (Réunion) by 1720 gave the Bourbon group.

Caribbean and Brazilian coffee was grown by enslaved Africans. In the eighteenth century slave plantations grew coffee in Martinique, Suriname, Jamaica and above all the French colony of Saint-Domingue. After the enslaved people of Saint-Domingue rose in revolution in the 1790s, Cuba and Brazil filled the gap. In Brazil's Paraíba valley, the historian Rafael Marquese shows, about 560,000 enslaved Africans were landed in the centre-south of the country between 1811 and 1830, and about 546,000 more between 1835 and 1850, when the trade was already illegal. Estates with more than a hundred captives each produced most of Brazil's coffee, and planters organised the land to extract as much labour as possible. From the 1830s Brazil dominated the world market. Slavery there was not abolished until the Lei Áurea of 1888.

In 1869 a new disease was described on coffee leaves in Ceylon and eastern Africa: coffee leaf rust, caused by the fungus Hemileia vastatrix. Soon after its first report, a 2017 review by plant pathologists in Lisbon notes, the disease wiped out coffee cultivation in Ceylon, with devastating social and economic consequences; the botanist Harry Marshall Ward, who studied the epidemic at the time, linked its severity to the intensity of planting. Planters turned to tea (see the history of tea).

The rust spread to nearly every coffee region by the mid-1980s. Since 2008 a cluster of epidemics across the Americas, which the historian Stuart McCook and the ecologist John Vandermeer call "the Big Rust", has hit producers and labourers hard. Growers have answered with resistant varieties found in the wild, breeding, fungicides and changes to how farms are managed. After the Second World War governments and international bodies built a network of coffee research institutes, which McCook and Vandermeer credit with helping farmers live with the disease; the hardest problem now is making control both ecological and affordable for small farmers in a volatile market.

The International Coffee Organization counted world production at 168.2 million 60-kg bags in coffee year 2022/23 and forecast 178.0 million bags for 2023/24, about 102 million of Arabica and 76 million of Robusta. Since the 1970s a "specialty" sector has grown around beans of known origin and high quality; the Specialty Coffee Association credits Erna Knutsen with coining the phrase "specialty coffee" in the Tea & Coffee Trade Journal in 1974. The American and European specialty coffee associations merged in 2017 to form the Specialty Coffee Association. The genome work adds a warning: cultivated Arabica descends from very few Yemeni plants and has little genetic diversity, which leaves it exposed to disease and a warming climate.