This is the first entry of two that I will make on the evolving meaning of the term ale from the advent of hops in England to the modern day. The first entry will cover the period from approximately the start of the 15th century to the beginnings of porter brewing in the first half of the 18th century.
Today when we think of the word ale, the most accepted definition is one that distinguishes ale from lager based on the fermentation conditions and yeasts that make the two beers. Ales are made with top fermenting yeasts at higher temperatures, and lagers are made with bottom fermenting yeasts at lower temperatures. Both lagers and ales can be described as beers. Yet in England, from the advent of hops in beer in the early part of the 15th century until perhaps the first half of the 20th century, ale was distinguished from beer based on the amount of hops used, color, or alcohol content. This is in slight contention with the conventional understanding that once hops became universally used a couple centuries after their first arrival in England, the words ale and beer became effectively synonyms. This is not the case. Even after hops were used in almost all fermented malt beverages, the term ale was understood to be a beverage that was less hopped than the closely related, but more bitter, beer.
The earliest word for ale was introduced to the English-speaking world by the Danes, who called their beverage øl. This became ealu in Old English before finally settling on the now familiar ale. Beer, on the other hand, first showed up in England around the beginning of the 15th century, when German-speaking settlers brought their hopped brews from continental Europe. The German word bier eventually became beer, which distinguished it from the unhopped ale.
Hops were very late in arriving to England. The first known use of hops in brewing was from 822 AD when the Benedictine monk Abbot Adalhard recorded that his monastery in northeastern France used hops. By the 11th century hopped beer was the norm in France, with King Louis IX going so far as mandating in 1268 that only malt and hops be used in the making of beer. As hops became prevalent throughout Europe, England remained ignorant to its use. Once introduced to hops, however, the English were reticent to use the flower in their native brews. For the most part, the English viewed hops as an unwholesome plant to be devoutly ignored. Two English kings, King Henry VI and King Henry VIII, in the 16th century went as far as to ban the use of the plant outright. Henry VIII justified his stance in the 1530's by proclaiming that hops were an aphrodisiac prone to drive his subjects to sinful behavior.
Such sentiment against the hop was likely a significant factor in keeping the terms ale and beer separate. Eventually, the benefits of hops as a preservative and a flavoring agent persuaded the English to adopt it in almost all of their brews by the first half of the 18th century. Even so, ale was still distinguishable from beer. The first edition of the London and Country Brewer in the 1730's described the difference between ale and beer based on their recipes, particularly with regards to the amount of hops used:
For strong brown ale brewed in any of the winter months and boiled an hour, one pound is but barely sufficient for a hogshead [54 gallons], if it be tapped in three weeks or a month. If for pale ale brewed at that time, and for that age, one pound and a quarter of hops; but if these ales are brewed in any of the summer months there should be more hops allowed. For October or March brown beer, a hogshead made from eleven bushels of malt boiled an hour and a quarter, to be kept nine months, three pounds and a half ought to be boiled in such a drink at the least. For October or March pale beer, a hogshead made from fourteen bushels, boiled an hour and a quarter and kept twelve months, six pounds ought to be allowed to a hogshead of such drink.
It was about the same time that a new type of beverage was gaining popularity that would become known as porter. Together with ale and beer, porter would become the third leg of the fermented beverages in England, with many pubs of the day (and even sometimes in England today) displaying that they serve "Ales, Beers and Porters".
Up next, the evolution of the meaning of ale through the rest of the 18th century through to today. We will see that ale eventually became less distinguishable from beer based on hop character and more so on color through to the first half of the 20th century. In the second half of the 20th century, ale would finally take on the definition that we know today.