India pale ale (IPA) is a beefed-up version of pale ale, made using more hops and with a higher alcohol content. Created in England, the name is a result of its popularity with British troops stationed in India in the 19th century, when the subcontinent was still a British colony. However, there is some dispute about exactly how and why it was invented.

The most popular theory is that IPA was created to survive the tough, months-long trip from Britain to India through tropical weather with no refrigeration. “They upped the hops and [alcohol by volume in pale ale], and the beer not only made the voyage, but the troops loved it,” says Julia Herz, the craft beer program director at the Brewers Association in Boulder, Colorado.

Others dispute how much difference a little extra hops and alcohol would make in such extreme conditions, and say that it was a simple matter of taste: While normal pale ale arrived stale and flat, with off-flavors ranging from cardboard to rotten vegetables, these flavors were masked by the bitterness and smell of extra hops in IPA, says George de Piro, the brewmaster for C.H. Evans Brewing Company at the Albany Pump Station in New York. As for the higher alcohol percentage, he speculates that “it probably kept the people on the other end happy that were drinking it—you’ll get intoxicated much faster and maybe forget you are posted far from home in India.”

These days, many popular British IPAs—such as Greene King and Deuchars—are largely indistinguishable from other pale ales or bitters in terms of hops and strength. However, on this side of the Atlantic, strong, hoppy IPA has become a signature style for many American microbrewers. The beer now accounts for around 8 percent of all craft beer sales, according to market research firm Information Resources Inc. This is because more American beer drinkers are becoming interested in the assertive bitterness and interesting flavor interplay between hops and malt that IPA offers, says the Brewers Association’s Herz.

CHOW’s Nagging Question column appears every Friday. Got a Nagging Question of your own? Email us.